Name A anime Where.

Inu Yasha

Dramatical Murder!!!!! heh :P

...Yugioh GX?

Aesthetica of a Rogue Hero

fecha A Live

sousei no onmyouji for sure.

Alice in the Country of Hearts. It's pretty much a world of kill-or-be-killed and lives don't matter, and everyone falls in amor with Alice, because she's an Outsider and has a beating corazón instead of a clock, which is what the residents of that world have.

Chivalry of a Failed Knight