This is just all based on my theory! And sorry for spelling mistakes
But would he hide him just to beat up his bullies? Like, for it to be so traumatic maybe is something more serious, maybe something about their families? But also weird that the trigger make him want to suck like damn
Its a bit wierd but it isn't that much of an surprising reaction if u think this theory is true. After feeling the scent of somebody you've been longing for who knows how many years ofc you're gonna want to be intimate with that person
I feel like the scent he's been looking for all along is definitely from the uke, most likely the uniform he used to wear when he was still in sports. We can see a bit of flashback where I can conclude they already met back when they were younger, where ml is told to hide and seek with a person we can see who wears the same uni as uke. And uke did mention he was an early bloomer back when he was still into sports. I think ml used to get picked on back then and then uke helped chased them off but somehow forgot about ml due to the incident 2 years ago where we can see his head bleeding from the argument he had at the pc cafe.
Ml probably got ptsd from then, probably waited for uke to come back for him to then he forced himself to stay awake, since he couldn't go out, he used his nose to try and track the scents passing by, which messed up his sense of smell? And the ptsd made him unable to sleep unless he literally passes out. And made him have insomnia whenever he tries to sleep.
Now we see on chap early chaps that he somehow fell asleep just from uke's scent, therefore brungs us back to the theory, he can finally sleep feeling safe in uke's embrace.