User Recommendations for Deadman Wonderland

Both are gritty, and violent with a soft-hearted main character who gets dragged into a plot larger than himself. Both series use a power system that is unique to each character and there are varying forms of alliances and team-ups. Both have largely unexplained supernatural or illogical set-ups for their existing systems but are fun to watch.

Student joins hell of a world. Partnered with a crazy powerful female. Both protagonists have to try to escape the hell they dwell in.