I heard jaemin is in love with soohyun & he's trying every possible method to break apart Daon & soohyuns relation by manipulating Daon emotionally...actually soohyun is kinda psyco ,he is threatening Daon that he's gonna hurt seohyun (the black hair puppy seme) & previously soohyun did hurt someone who was close to Daon during college that's why Daon is very scared of him & has no choice but to meet whatever soohyun says but they r not dating or anything coz Daon donot like him at all,, he just has to listen to him coz soohyun keeps threatening non stop
Seunghyun puppy seme...I got his name incorrect
Actually the real psycho is the sunbae Jaemin. In college he figured out that Soohyun was into Daon and he also knew Daon only has eyes for him. SH saw this too n didn’t like Jaemin. So Jaemin suggested that SH date him so Daon will gain interest in him. At that point daon didn’t give a flyin fuck abt him. So then they start dating and all the messed up relationship.....
So like what kindv relationship does daon and souhyun have now is he like his sugar daddy cuz his always at his apartment
Spoiler
So from my personal research and comprehension the meaning behind the title is the secret relationship between daon and souhyun(toxic seme ) who's yet to appear cuz as you can see in the comic's poster he's not showing despite being the source of all the drama and playing a massive role in the comic
So jeamin"tutor" And souhyun(toxic seme )used to date in college or had a sort of an intimate relationship I don't know if they're still a thing in the present but now souhyun and daon are in an affair and I'm 99.99% sure they sleep together specially from the fight scene in the raws ,so soohyun threatens daon that he'll tell jeamin about their secret affair if daon tried to break things off and we known that daon loves and respects jeamin dearly so of course he'll do what he's soohyun said
And to that also explains why I always see the three of them in the same apartment but never together
And I know that jeamin knows about them but just playing it and he's not an
angel he sure is SUS
This is all a theory I'm not sure