Novel Link and Spoilers

I really, really liked the comedy in this series and they both gave mad virgin energy despite being in their late twenties and early thirties so I went on a mad search for spoilers to see if that was true. I found the original Korean novel on google playstore books, link here:
https://play.google.com/store/books/series?id=ZR5GHAAAABAiAM
And spoilers:
In the novel they are both virgins, completely. Joohwan briefly dated a woman but couldn't have sex with her and got broken up with because he made her feel unwanted. And Sihyun as he got older attempted to sleep with a woman but couldn’t go through with it because of a certain someone. In fact Joohwan affected his sexual tastes and he became into being strangled lol, but only by Joohwan. After they do the deed in novel 2, both thinking the other had a lot of experience lmao, Sihyun thinks to himself that if he knew sex could be this good, he would have done it a lot sooner. Also, Sihyun thinks Joohwan is engaged and Joohwan doesn’t bother to clear this up until end of novel 3, when Sihyun gets engaged because of his family and Joohwan gets very upset and lets Sihyun know he doesn’t want Sihyun to get married marriage and confesses his feelings and virgin status to him lol. Sihyun thought being in a fake marriage was okay bc of his own parents and bc he thought Joohwan was already engaged to someone else but still doing it with him. It was also very funny when Joohwan blamed Sihyuns masochistic tastes on his nonexistent previous partners but then Sihyun tells him that his only partner has been Joohwan and Joohwan was the one who developed Sihyuns sexual tastes lol