not to be one of those "ephebophile isn't the same as pedophile!!!!!!" people but jace is probably attracted to younger chicks because his entire persona revolves around being this badass stoner/parkour/skater super youthful guy - as opposed to a preference for children. an unemployed 16 year old that skates and smokes weed and lives with his folks is average, a 23 year old man in that situation on the other hand, is pretty weird. jace will do anything to escape that reality. hell, he posted a tweet about getting a haircut, with #lifeteen, when he hasn't been a teen in four years. don't get me wrong though: it's creepy as fuck regardless of reasoning.
single adult women tend to have jobs or an education, actual friends, their own place, the ability to not be impressed by cheap vodka and reggie etc etc. plus, they've probably had boyfriends that have had those things. that shit probably terrifies jace. it's way easier to liquor up 17 year old girls and buy rogaine. (not saying jace could even manage that, we've yet to see any proof of anything. my islams are on virgin.).
damn i'm off topic