Continuing on my musings which character Ian and Lena prefer over others in sex, I estimate it goes along this:
Lena: Axel-Jeremy-Mike-Ivy-Ian-Robert-Holly-Louise-Stan
Axel is a sexgod that knows her for years and haunts her in her dreams, her obsession with Jeremy is probably the only thing that can rival it (I forgot how the second masturbation scene plays out, it could be that Jeremy even beats Axel in it). Mike and Ivy are sex freaks. Ian mostly wins by being romantically comforting, Holly likely as well. Robert is mostly a stand-in to put of some steam, he can beat wimp Ian, but if the latter puts some effort in sex, then he is beaten. I put Holly above Louise, because Lena seems to be more the giver to Louise than the receiver, she likes the dominative aspect of having a pet. It's obviously even more extreme with Stan, she just gets off on someone masturbating to her.
Ian: Cindy-Minerva-Bad Jessica-Ivy-Lena-Emma-Cherry-Good Jessica-Alison-Holly
Cindy tempts him to betray his friend. Minerva has high lust stats and appeals to his dominant chad side and he notes how wild the affair is. He goes nuts over Jessicas porns and he notes how Ivy is unobainable and above his reach.Lena is the most beautiful girl he met and also intellectual appealing, he stops having fun with Emma for her. Emma can win him over Alison in the club and he gets off on the childhood friend angle much more, he can also tease Alison by noting that Cherry dresses sexier. Though Cherry is currently mostly about comforting. Alison is supposed to be a bit plain and awkward and Ian doesn't seem to be a big boob guy. He dated a flatty and almost all of his girls aren't extremely developed. Holly is plain and he is mostly interested in her intellectually and romantically.
Don't know about Gillian, since they have yet to tell us exactly what their deal was. It may not be an overly sexual but very emotional relationship.