Styl - I like his character design and Innocentius is just awesome.
Misaka Mikoto- duh, She's probably the reason why I couldn't drop the series during the early episodes.
Accelerator- What? I like characters that are sadistic, fucked up, bat shit crazy, overpowered characters and his unique power is a huge plus.
Sphinx- Because of him/her(?) I'm starting to see the adorableness of cats
