Ajin: Shoudou

Kei discovers the curse of immortality when he gets hit by a bus... and doesn't die. Now on the run from a government that wants to experiment on him, and his fellow Ajin, Kei's only hope to live a peaceful life lies in his ability to learn how to use his new powers. Aided by the strength of his "Black Ghost", a once apathetic Kei must now fight to avoid becoming a cruel demi-human experiment.

(Source: Sentai Filmworks)