It was OK. You needed a bit of suspension of disbelief for this - I found the scenario in which they meet and wind up living together to be a bit farfetched. For a book with a title and cover about rules there was not much emphasis on these rules throughout the book at all. (If you want a story where the roommate is regimented with his ridiculous house rules but slowly makes exception foe the FMC as he realises he loves her type story, this is not it. Honestly the rules were very typical normal rules for roommates/strangers to have? Other than the weird TV one...) I thought the banter was extremely forced and cringeworthy to read in places. And the passage of time was really weird, I honestly couldn't tell if it had been weeks or months that they had been living together. Most likely because nothing major or significant really happens in the story. Nick, douchebag that he is, only seems to be there in order to place doubt in the FMC's head at the end of the story which leads to a weird I'm-not-gonna-assume-so-I-just-won't-ask miscommunication trope.
Don't get me wrong, it was cute, it has a happy ever after, the eventual tension between the two was quite well written, it's an easy read so I ended up reading it in one sitting, and you do catch glimpses of both MCs' moments of vulnerability which helps them to understand each other more. I just couldn't look past all the above to give it any higher a rating. Sorry!