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The Billionaire's Forbidden Little Sister (Billionaire Collection Book 4) Kindle Edition
More important question: How long can you keep it a secret before it all goes up in flames?
Two strangers in a foreign country, we said hello.
Hello turned into a kiss.
A kiss turned into a rendezvous.
And a rendezvous turned into more than I'd ever imagined.
But her unruly golden curls and beautiful body hid an important detail—She's my mouthiest best friend's little sister.
If a newspaper was covering my current debacle, it’d probably look something like this...
BREAKING NEWS:
Theo Cruz, a New York man known for his family's billion-dollar empire, Cruz Enterprises, has been indicted this afternoon in the Court of Public Opinion on charges of Bro-Code Conspiracy.
Chief counsel for the prosecution, Caplin Hawkins, spoke candidly about the accusation. "Once thought of as a best friend to many—including myself—Theo Cruz has officially turned his back on human decency. He's conniving and dishonest, and a habitual offender of Bro-Code Law 676. He'll rue the day he forgot that you never—under any circumstances—get involved with your best friend's little sister."
Obviously, I haven't been arrested or indicted, but it’s safe to say, I inadvertently messed up—big-time. And even though I know I’m playing with fire, I can’t stop.
I have to make her mine.
Disclaimer: The Billionaire's Forbidden Little Sister is a romantic comedy, NOT a taboo romance. We repeat: It is NOT about a billionaire canoodling with his own sister. However, if you find yourself wishing it were, we suggest switching around some names to make it so. We can't guarantee it won't be confusing at times, but who knows? It could be just what your doctor ordered.
- LanguageEnglish
- Publication dateNovember 5, 2019
- File size3.0 MB
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See full series- Kindle Price:$17.97By placing your order, you're purchasing a license to the content and you agree to the Kindle Store Terms of Use.
- Kindle Price:$23.96By placing your order, you're purchasing a license to the content and you agree to the Kindle Store Terms of Use.
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This option includes 4 books.
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Editorial Reviews
Review
"An utterly charming blend of sweet, sexy romance and laugh-out-loud humor, The Billionaire's Forbidden Little Sister is exactly what readers crave from this author. I smiled from ear-to-ear the whole way through as I practically inhaled this book." -- Red Cheeks Reads
"This book was pure gold. I was dying of laughter from the first chapter to the end, but there was also plenty of steam and swoon worthy scenes mixedin." -- Book Addict Reviews
"This story was off-the-charts when it came to chemistry! Holy Cow!!!" -- Keri Loves Books
"WOW WOW WOW. I seriously couldn't put this one down." -- Ra Ya Bookreviewers
"This is another classic, mad-cap, laugh-out-loud (and yes, WARNING... NSFW) read that with leave you feeling more than satisfied, in all the right places. One-Click this HOTTIE today." -- GhostPepperBabes/ Pimpers' Dungeon
"Theo and Lena are absolutely perfect together. Their chemistry will heat up the pages of your kindle and leave you fanning yourself for hours. I loved this one." -- Southern Vixens Book Obsessions
"Max Monroe takes addictive reading to new heights. The Billionaire's Forbidden Little Sister may put a strain on the bro code, but the chemistry between each and every character puts it at the top of my 2019 MUST HAVE list." -- Hopeless Romantic
"It was the perfect mix of sweet, steamy, and absolutely hilarious! Gahhh! So perfect!" -- Messy Bun Book Blog
"My favorite book of this series. Laugh out loud, tears running down my face favorite." -- Sherry, Goodreads reviewer
"Gather your Kleenex because you're gonna laugh until you cry! Another Max Monroe MUST READ!" -- Melinda, Goodreads reviewer
"You two nail the RomCom genre and set a very high bar for others. The Billionaire's Forbidden Little Sister is one of the funniest books I have read this year and I cannot wait to listen to it on audio." -- Erin, Goodreads reviewer
"From the blistering chemistry, that could easily set the sheets aflame, to the hysterical references that only Max and Monroe could conjure, I just could NOT get enough." -- Ashley, Goodread reviewer
"The queens of romcom have gone and done it again with this hilarious laugh out loud entertaining read." -- Jackie, Goodreads reviewer
"I loved The Billionaire's Forbidden Little Sister! This book was absolutely hilarious and it ticked all the boxes for me." -- E, Goodreads reviewer
Product details
- ASIN : B0813XDH8N
- Publisher : Max Monroe LLC
- Accessibility : Learn more
- Publication date : November 5, 2019
- Language : English
- File size : 3.0 MB
- Screen Reader : Supported
- Enhanced typesetting : Enabled
- X-Ray : Not Enabled
- Word Wise : Enabled
- Print length : 355 pages
- ISBN-13 : 978-1732170278
- Page Flip : Enabled
- Book 4 of 4 : Billionaire Collection
- Best Sellers Rank: #44,646 in Kindle Store (See Top 100 in Kindle Store)
- #2,073 in Romantic Comedy (Kindle Store)
- #2,573 in Romantic Comedy (Books)
- #6,945 in Contemporary Romance (Kindle Store)
- Customer Reviews:
About the author

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Website ➜ www.authormaxmonroe.com
New release text alerts ➜ Text MAXMONROE to 21000
Many moons ago, a dynamic duo of romance authors teamed up under the pseudonym Max Monroe, and, well, the rest is history...
Max Monroe is the New York Times and USA Today Bestselling Author of over thirty contemporary romance titles (with Romantic Comedy being their jam), Favorite writing partners and long time friends, Max and Monroe strive to live and write all the fun, sexy swoon so often missing from their Facebook newsfeed. Sarcastic by nature, their two writing souls feel like they’ve found their other half. This is their most favorite adventure thus far.
Customer reviews
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To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyzed reviews to verify trustworthiness.
Learn more how customers reviews work on AmazonCustomers say
Customers love this book for its heartwarming and light-hearted romance, with one review describing it as a "foreseen forbidden love" story. Moreover, the book receives praise for its humor, with customers laughing out loud multiple times, and its well-developed characters that maintain their personalities through actions and dialogue. Additionally, the writing is easy to read, and customers appreciate the good amount of steamy content.
AI Generated from the text of customer reviews
Customers find the book readable and enjoyable, with several mentioning it's part of a series they love, and one customer particularly appreciating the story between Lena and Theo.
"...This is where the story gets even better! Buy the book to find out the shenanigans that follow!" Read more
"...Fun and flirty not only do we get to watch the relationship between Theo and Lena unfold but we also get to catch up with all the other characters..." Read more
"...Imaginative plots coupled with endearing characters embroiled in these deliciously sexy romances that are heart-tugging and heart-warming, and this..." Read more
"This book was amazing. I am so glad Max & Monroe brought back the book club...." Read more
Customers find the book hilarious, with multiple reviews mentioning they laughed out loud more than once. One customer particularly appreciates the great banter throughout the story.
"Max and Monroe weren’t kidding when they said this book was funny. There are times I was laughing out loud, and my husband looks at me like I’m nuts...." Read more
"...An utterly charming blend of sweet, sexy romance and laugh-out-loud humor, The Billionaire’s Forbidden Little Sister is exactly what readers crave..." Read more
"I loved this series! It was so funny I was constantly hiding my mouth in my shirts so people couldn’t see me laughing while reading this series!..." Read more
"...Humor Sex, In just about every other ingredient it takes to make good books...." Read more
Customers enjoy the romance in the book, describing it as swoon-worthy and super romantic and extremely funny, with one customer highlighting the heartwarming tale of unforeseen forbidden love.
"...Anyhoo, this is another hit for the fantastic duo! Theo Cruz is on his way to Positano, Italy for the grand opening of his new club...." Read more
"...An utterly charming blend of sweet, sexy romance and laugh-out-loud humor, The Billionaire’s Forbidden Little Sister is exactly what readers crave..." Read more
"...of a multi-billionaire tycoon, grew up with a golden spoon, she was kind, compassionate, and caring...." Read more
"...Lena and Theo are such a great couple." Read more
Customers praise the character development in the book, noting that the characters are brilliant and kept them laughing throughout the story. One customer particularly appreciates how the characters maintain their personalities through their actions and dialogue.
"...This is a great series of men who find their one and only's as written as only Max Monroe can do it." Read more
"...I love this family of characters And look forward to the books following. Highly recommendPoint" Read more
"Well this was just a fun book With likable characters. It is a fast read It would make a good beach book." Read more
"...Thatch is still my favorite character. His little additions make these books. The Book Club is still going strong and plays a big part here...." Read more
Customers find the book sexy, describing it as gorgeous and funny with good amounts of romantic scenes.
"...Turns out he’s not only gorgeous but also funny. While dancing and getting to know Theo, she notices a disturbance at the DJ booth...." Read more
"...This is when she meets Theo. Handsome, debonair, Theo… Things start to heat up with just a kiss, until Pippa turns in to a sloppy drunk and Theo..." Read more
"...Fun and flirty not only do we get to watch the relationship between Theo and Lena unfold but we also get to catch up with all the other characters..." Read more
"...Written in dual first person POV. Lots of humor and good amount of sexy times. I’m happy that MM continued the book club - hilarious...." Read more
Customers praise the writing quality of the book, finding it very well written and an easy read, with one customer noting the great editing.
"...to the creativity of this author duo, and speaks volumes about the quality of their writing...." Read more
"...These books are so well written that I feel like I'm a part of the story...." Read more
"...mostly 4’s, a book needs to be like “wow” and beyond for a 5 but editing was great, loved the light hearted story, however felt like the end was..." Read more
"...Why? Because every single word they write is gold & it’s definitely money well spent...." Read more
Customers find the book heartwarming and light-hearted, with one customer noting it has no angst.
"...Fantastically well executed, light-hearted and fun, I smiled from ear-to-ear the whole way through as I practically inhaled this book...." Read more
"...This book is light, no angst, and steamy hot 🔥🔥🔥, though I feel like it’s missing the typical LOL elements as seen in the previous books, and I wish..." Read more
"...What a hoot!" Read more
"...Omg... There was so much fun and light heartedness that this one is easily my favorite!..." Read more
Customers enjoy the steamy content of the book.
"...This book is light, no angst, and steamy hot 🔥🔥🔥, though I feel like it’s missing the typical LOL elements as seen in the previous books, and I wish..." Read more
"...Not as funny as some of their books, but very hot and fun!!" Read more
"...still angry with her and how it all went down, but they are insanely hot together and I was happy to see their HEA...." Read more
"This story was HOT! HOT. Italian fling, sailing through life billionaire, and a group of rowdy friends...." Read more
Reviews with images

Erry body n da world need to read Max Monroe eee!
Top reviews from the United States
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- Reviewed in the United States on November 16, 2019Format: KindleVerified PurchaseMax and Monroe weren’t kidding when they said this book was funny. There are times I was laughing out loud, and my husband looks at me like I’m nuts. Anyhoo, this is another hit for the fantastic duo!
Theo Cruz is on his way to Positano, Italy for the grand opening of his new club. He needs to make sure everything runs smoothly.
Lena just took her finals at a design school in Milan, and she and her fellow besties go on holiday to Positano for a week of fun and sun to celebrate. While hanging out at the pool of the resort, they get VIP passes to the grand opening of a hot new club in town. Her roommate and new best friend, Pippa, is on a roll tonight, drinking shots of Tequila, something she’s never tried before. Tonight Lena is breaking her no man rule, after nine months. When Lena spots a gorgeous man standing by the bar, she decides to approach him. Turns out he’s not only gorgeous but also funny. While dancing and getting to know Theo, she notices a disturbance at the DJ booth. It’s her roomie trying to take the microphone away from the DJ. Yikes! Lena needs to get Pippa back to the resort before she ends up in an Italian jail. With the help of Theo, they manage to get her down and back to the resort. There goes her chance to hookup with the handsome Theo.
The next morning Theo is having coffee on the balcony of his room when he spots Lena relaxing by the pool. He needs to see her again, so Theo decides to write a note and has it delivered to her by one of the resort employees. Hopefully she also felt the connection they had and agrees to see him at 11pm by the pool.
Skinny dipping in the pool is not something Theo saw happening, but this girl is spontaneous and sexy as all that. Alas, everything was going great till Pippa, who is drunk again, decides to also hang out by the pool. Another night shot to hell by the very entertaining Pippa. This is not going to stop him from spending more time with Lena. So for the remaining days of her holiday they become really close and inseparable. The only problem is that Lena makes these ridiculous rules that they don’t share any personal information and no last names. On their last day at Positano, Lena makes a cowardly move and leaves him a goodby note instead of doing it face to face.
Now that they are both back in New York City, this is where the story gets funny. Theo can’t stop thinking about Lena and he does something he’s never done before. Goes on the web to try to find her by posting a note, hoping she will read it and contact him.
One of his best friends, Cap Hawkins, tells Theo that they are going to a fashion show, to see his little sister who is working for one of the top designers in the city. No matter how hard he tries to get out of it, Theo knows he’s lost this battle. After the show they go backstage, and to Theo’s shock, Cap’s little sister is no other than Lena! This is where the story gets even better!
Buy the book to find out the shenanigans that follow!
- Reviewed in the United States on November 8, 2019Format: KindleVerified PurchaseI’ve wanted a story about Lena Hawkins since she was introduced in My Brother’s Billionaire Best Friend, when we met her at the coffee shop that her father bought for her when she turned 18, where Maybe Willis liked hanging out. Right away, I knew she’d be a great leading lady. Sister to Caplin Hawkins, overprotective brother and Billionaire Lawyer to too many CEOs to name (most of the Billionaire series heroes included). Growing up wealthy didn’t do Lena any favors with figuring out what she wanted to be when she grew up. Having Victoria Hawkins as a mother, difficult to say the least, also factored in her life choices. Thankfully, her brother and father always had her back. At the end of Maybe’s book, Lena had decided to go to Fashion School in Milan, Italy.
This story opens nine months later with Lena and a couple of classmates celebrating the end of their exams, before heading off in different directions for their 3-month internships in the Fashion Industry. Thankfully, Lena’s headed back to NYC to intern with a great designer. They decide to go to a resort in Positano, Italy to spend have some R&R in the sun. Her classmate, Pippa talks Lena into dropping her “self-inflected man ban” on their first night, let her hair down and have a little fun.
This is when she meets Theo. Handsome, debonair, Theo… Things start to heat up with just a kiss, until Pippa turns in to a sloppy drunk and Theo helps Lena get Pippa back to their hotel room to sleep it off. They try again the next night, where they get a little steamy in the pool, but once again drunk Pippa makes an appearance. When they finally get together, sparks fly and they spend as much time together as they can. Early on, they agree not to exchange names and personal information. When her vacation ends, so does their time together. Lena finds it too hard to say goodbye in person, so she leaves a note for Theo with the front desk.
This guy she spent all her time with is none other than Theo Cruz, part of the Cruz Empire, founder of all of the Cruz Nightclub, Billionaire… and one of his best friend’s is Lena’s brother, Cap. Theo gets back to New York to enjoy the co-ed Bachelor party thrown for his friend’s Milo and Maybe (yes, that Maybe). It’s there he comes face to face with Lena. Knowing how Cap feels about his sister (remember I said he’s overprotective), Theo pretends to be meeting her for the first time.
The heat is still steamy between them, but they know they need to keep it quiet to not wake the Caplin Beast, at least until they come to terms with what they have together. And once Cap figures it out, Theo better beware. But he isn’t the real issue in their relationship. During a dinner with the Hawkins’ family, Lena has a run in with her mother, which leaves her unsettled enough to break Theo’s heart.
Can Lena really have it all? A career she loves and a man, as well. Or is she just kidding herself thinking she can make it in the world of Fashion? You just need to read this book to find out. Once again, we have appearances by all the Billionaires and a return of The Billionaire Book Club. If you love to laugh, this fluffing series is definitely for you!
- Reviewed in the United States on December 29, 2024Format: KindleVerified PurchaseI guess we all like to imagine what it would be like to date and marry a billionaire. I get tired of the formula. Meet, fall in love, break up, get back together. I challenge the authors to break that convention. Lots of authors do.
- Reviewed in the United States on November 10, 2019Format: KindleVerified PurchaseLena was raised in a privileged lifestyle but she is determined to follow her own dreams and not give into the pressure that is being levied by one parent in particular. She has been studying fashion in Italy for the last nine months and is will be heading back to the US soon. Now that her studies have come to a close her friends have convinced her to have some fun before that happens and Theo is the perfect man for the job.
Theo was attracted to Lena the moment he saw her and after a few false starts the chemistry between them ignites. They both know that this will be nothing more than a fling as they are both destined to go their own ways so sharing information about each other is off limits.
Now that Theo has returned home the surprise is on both him and Lena when they realize their fling didn’t stay in Italy as she is Cap’s little sister and Cap happens to be Theo’s best friend. They know they should stay away from each other but that is easier said than done and that is when the fun really begins!
Fun and flirty not only do we get to watch the relationship between Theo and Lena unfold but we also get to catch up with all the other characters that we know and love.
- Reviewed in the United States on January 9, 2025Format: KindleVerified PurchaseHey author, you still have the last hold out in the group to find love. Will he be in a new series or a stand alone? Can’t wait to read how you bring Harrison down ad with whom, is it
Papa by any chance? Haha she’s a riot.
Top reviews from other countries
- Michelle CReviewed in Canada on November 8, 2019
5.0 out of 5 stars Another great Max Monroe romcom
Format: KindleVerified PurchaseI'm dubbing Max Monroe the Queens of romcom! This is another hilarious book by the author duo.
What happens when you have a fling and she turns out to be your best friends little sister? Theo is going to find out! Theo and Lena meet while vacationing in Italy and have a week-long fling. Little does Theo know that he's breaking bro-code by having a fling with Cap's little sister Lena, who he's never met. We meet a couple new characters I hope to see again and also see a few old faces aka the funniest book club ever! I was definitely trying to not laugh out loud in public... Again. Max Monroe don't disappoint!
- Lainey SReviewed in Australia on November 6, 2019
5.0 out of 5 stars The best so far!
Format: KindleVerified PurchaseFrom the first page I was hooked! Max Monroe has a way with words, the true description of character and scenery that lets you be a part of the action. this romance between Lena and Theo is steamy, hilarious and filled with action that makes it impossible to put down.
Be ready to snort with laughter, shed tears of both joy and (for a little time) sadness. Out of all of the books for this Billionaire series, this is by far my favourite. You would be crazy to miss it!
- Di DReviewed in the United Kingdom on January 14, 2020
5.0 out of 5 stars Another laugh out loud book
Format: KindleVerified PurchaseI have loved this series just as much as the Bad Boy Billionaire books. Lena and Theo were brilliant, add in the crazy brother (not sure who had the craziest brother) as well as Theo's Grandpa, and you have comedy gold. I wish there was more with Brogan and Grandpa Merl.
Lens's brother, Caplin is so over protective of his sister, it's a wonder he lets her have her own apartment! That said, he makes any scene he is in, hysterical.
Theo is a genuine good guy. Level headed, hard working, caring and kind. He is one in a billion.
- Sulina MishraReviewed in India on December 31, 2024
5.0 out of 5 stars Great Storyline
Format: KindleVerified PurchaseFinally a story where the girl is not under pressure by the man or waiting for the man. Loved the concept and the way it unfolded.
- Anja DettmannReviewed in Germany on November 18, 2019
5.0 out of 5 stars Lena and Theo ♥️
Format: KindleVerified PurchaseLena - Cap's little sister - and Theo - Cap's best friend - are falling hard for each other.
Thank you (okay, not so thank you) to Harrison and Cap Theo will be constantly reminded of the Bro Code: a Bro's sister is a forbidden fruit - especially Lena.
I so enjoyed their journey from 'The Italian Rendezvous' to a 'relationship' without labels to love.
It's been a really fluffing funny and sizzling hot journey. 💗