Leo canonically self-harms (bite marks on his hands; it's easy to imagine him doing other things like scratching himself) during his shut-in days so we know he's definitely the type to cope through unhealthy ways... (well, if self-harming can be called coping)

but yeah to me leo has become so thoroughly linked to sex i couldn't imagine it any other way. He loves people, he loves feeling close to people, he's casually affectionate and a lot of his character design relies on him being seen as small and cute (and even girly). So it makes sense in my mind that Leo soon realizes the attraction power he holds over others and uses that as an outlet! To me, his healthy way of coping would be like.... sex with loved ones, aka other enstars characters, esp ones he's close to? (izumi, eichi, knights in general etc.) and unhealthy coping mechanism is of course him letting himself be touched by randos </3 (this is about GFK) We've seen time and time again in canon that Leo has a shaky sense of value, and that factors in SO MUCH in him getting into sexual situations. Sex is a way to feel appreciated and useful: with friends and people he loves, it's a way to feel loved; with others, it's a fucked up way to find value beyond his artistic talent. Some part of him DOES realize he's being used, but Next Door has him basically saying straight that he doesn't think he can prevent that from happening again because he simply doesn't see it as a big enough deal. His way of viewing the world is genuinely fascinating and I really hope enstars canon will keep on giving us more of that.

Slightly related, but I've got several fics planned that will closely explore Leo's relationship to sex. One more canon based (a GFK/Leo fic) and the other which is my mobleo aftermath series, in which a traumatic event changes, in small and big ways than how I usually write him, how he views sex and makes it a true coping mechanism with him.

i can never make my thoughts about leo not unhinged but i hope what i have in mind is clear!