[Kafriel]

Definitely one of my favourite characters of all time, his development was simply amazing...

Spoiler for series spoilers:

From the very first episode he is faced with murder and time travel, and takes a worldwide organization head on...What truly made me like him though, are his decisions after the first half, you don't see many people willing to witness their loved ones die over and over in an attempt to save them. Got even better after his talk with Kurisu and the "man behind Suzuha's cell phone", didn't expect him to do that much...