Riot takes inspiration from other games and media. They just don't mention it because they could get sued. It was fine when they were a smaller studio but now that they're huge. Riot doesn't take risk like that anymore.
The new champion is a he: http://i.imgur.com/BzsnDX1.png
This was funny and sad but its so true... http://i.imgur.com/t3olnSy.png