Novel (not really spoilers)

I have finished the novel recently and oh my god it was so good. This shit is a masterpiece before its a bl.
Immediately I have to say that ofc Jaegyeom (MC) looks young but in reality is old, and in the novel it is explicitly said that he doesn't know his real age because he doesn't know when he was born and when he stopped aging but he should be between 19-21. He only goes to school because he was forced by Jeongju so his age was made up by him and the high school arc with Taehee (ML) being his teacher/librarian ends very quickly. So don't worry about it too much, it did felt a little weird. In korean the age gap is eliminated almost immediately because Jaegyeom talks to Taehee very casually (and rudely) but because english doesn't have casual and polite speech it's hard to catch that.
Once everything start to fit in their place, you will see how Jaegyeom and Taehee are literal soulmates. And that those two, Jeongju, Mesan and Yoo Namsaeng no matter how much time passes will always be a family.
Both Gyeom and Taehee's backstories are really sad, you will 100% cry. Also please don't hate Myojeong too much, you will see he had his reasons. It will probably be a long webtoon if they don't cut anything.

Scrolled through the comments to see what people were asking to answer some things and yes both the novel and webtoon are 15+, there are kisses but anything beyond that was just implied. Yes Jaegyeom slaps and punches Taehee many times, sometimes he deserved it but other times no... Taehee is a yellow leaning green flag i guess, he had red flag tendencies and desires almost yandere-ish as he is very calculative but most of the times he never really acted upon them as Jaegyeom is hard to predict hahah still very obsessed though, never did anything to hurt Jaegyeom though. Oh and the romance is veryyy slow burn, their first kiss is after chapter 100 of the novel lmao