That depends, do you want to have sex with this person? I personally don't think there is much that's worth fucking someone I don't like or want to fuck.
Are you fingering a supermodel for 5 liters of sandoz lsd? or are you sucking some HIV positive frat boy's dick for 3 hits of "triple dipped" nbome lol. do you trade sex for other things? lots of questions around this. gut reaction is "fuck no you idiot, see a counselor". LSD can also provide experiences so precious, holy, and foundational to your life, that I would think it would be worth the loss of a limb much less a little stretch for your sphincter. If those experiences were guaranteed i might be more inclined to think sex is most obviously worth trading for lsd; but it's not guaranteed. there's a really good chance you're not even going to get lsd out of this, but some other chemical. there's a large chance you won't even get fake stuff; you'll just get punked, and maybe beat up or worse, maybe filmed and sold on the internet. details matter
what's a hit cost, $5? just buy the damn thing. if you're so broke that you can't afford lsd, you should be trading sex for something like food or rent, if anything.
