Cause it's a guy on the internet so obviously it has to be a girl. From a guy's point of view, playing league with a girl is akin to taking a ride on a mythical dragon. Maybe the dragon gets hungry, so you both stop at an ice cream parlor drive through in space. Dragon gets triple chunk extreme maximum moose tracks because dragon lives on the edge, but the guy just buys vanilla or pistachio because he's boring. Eventually dragon takes guy home and the guy is like "That was fun, can we do it again?" and the dragon nods, but the dragon never shows up again because the dragon could tell the guy was boring according to his ice cream choice.
Just goes to show you; take a risk. Skip the vanilla ice cream and get something crazy like...rainbow dot fudge filled super star ice cream. Also don't skimp on the sprinkles.
Sorry, I got carried away. You know, sometimes I think I should write a book. Anyways, it has to be a girl because a giant chunk of viewers are guys, and guys (some of them) like girls. Pretty much it in a nutshell.
Edit: D: my story got downvoted ;_;