Chris' biggest obstacle to sleeping with a willing woman who isn't a hooker is that he's an unemployed NEET who lives with his mom in a hoarders nest. Despite what the loveshies say, it's really not that hard to get laid. Hell,
I've gotten laid, with someone I liked and was attracted to, and I have the social skills of a Magic Ring Bearer who lives in a cave and subsists on raw fish.
He still has many, many factors that lower his odds. His wardrobe, his bathing habits, his personality, the shitting his pants thing. But still, I know plenty of hideous, eccentric hillbillies who brew moonshine in an Ocean Spray bottle with a condom for a filter who still manage to get laid with non prostitutes and even find girlfriends. Chris is still several steps below that level, but despite what loveshies say, it's never too late and never too hard.
The fact he has never shown a interest in drugs in general is a good thing if you ask me (I haven't got a problem with it when your a adult an it's your choice) but Chris isn't mature enough to know when to stop and when it comes down to it he couldn't handle the effect of anything that screwed with your perception of reality.
Chris is just childish, not really a child. Hasn't he been tested on this before and it was proven he wasn't really a child in a man's body?
Besides, he's already tried psychiatric meds and booze, and he's never abused those to serious degrees. At least with the right strain of weed he might calm down a little, open up a bit more socially, and spend less money than the Legos and games run him.