Diana, Karma, Kayle, Lux (There was a ton of outcry when she was sexualized.), Shyv. That's 11 out of 31 or so, or 7/27 if you take the ones which are obviously un-sexualizable (Yay, butchered grammar) , which isn't that bad.
Let me count all the square-jawed manly men. Darius, Gangplank, Garen, Graves, Jarvan IV, Jax, Jayce, Lee Sin, Nasus, Pantheon, Tryndamere. That's not counting all of the other potentially over-sexified humanoid men.
W..what? Darius is fully clothed and displays nothing sexual or even implying sexuality... The only one I give you is Tryndamere. Either that or you have absolutely no idea what sexualisation is. Hint : It's not being huge and/or square-jawed. If you take square-jawed as sexualisation then I take "visibly having breasts" as female sexualisation and only the child-like characters remain unsexualised.
edit : You know what I might have an extremely important master's entry exam in university in two days but screw it.
Taken from wikipedia :
http://en.wikipedia.org/wiki/Sexualization"The sexualization of an individual or group refers to the acts or processes whereby the
individual or group is seen as sexual in nature[1] or a person becomes aware of their sexuality."
I've helpfully bolded the important part of that definition, since it's a pretty good definition and it serves well in our case, not to mention I can't find scientific papers on the definition of sexualisation right now.
Going by that, and narrowing it down to "huge exposed tits", let's count the number of female champions in LoL. Let's just go by default skin.
Ahri; Akali; Ashe; Caitlyn; Cassiopeia; Evelynn; Irelia; Janna; Katarina; LeBlanc; Lux; Miss Fortune; Morgana; Sejuani; Sivir; Sona; Syndra; Zyra. 18 out of 28 and I'm specifically exluding alternative skins (add Vayne, Diana, Riven and Nidalee) and skintight clothes (add Fiora). This leaves us with Leona - best LoL female design, Shyvana, Soraka and Orianna. I'm excluding the child-like yordles for obvious reasons.
All of these are sexy, slim ladies with huge breasts.
Let's check out how many male champions are even bare-chested.
Alistar, Brand, Mundo, Galio, Gragas, Kassadin, Lee Sin, Malphite, Maokai, Rengar, Ryze, Sion, Tryndamere, Urgot, Varus, Warwick. 16 out of 56.
Of those 2 are fat/bloated - Gragas and Urgot; 3 are animals - Warwick, Alistar, Rengar; 3 are inhuman - Galio, Malphite, Maokai; one is Mundo, and we have 6 left - Kassadin, Lee Sin, Ryze, Sion, Tryndamere, Varus.
A FAVOURABLE COMPARISON.
So... where are the non-colourswap inhuman females? Where are the fully armoured/clothed females? Where are the animalistic females?
See what I'm getting at when I say I want variety? And no I don't mean give me sexy furries. I mean copy god damn BLC's Guardian because holy shit Sejuani is bad design made flesh.