RWBY: Under an Empty Moon

They call him the Black Moon.
A young man who survived one hundred duels to the death and ended the last with a single draw.

Tsuki Kuroi fights with a philosophy older than Remnant itself. To activate his Semblance, he must become empty, emotionless, and perfectly still within one microsecond. The stronger his feelings, the weaker his blade.

When he is recruited into Beacon Academy, Tsuki is forced into a world built on teamwork, hope, and heroism, ideals that threaten the very mindset that keeps him alive.

As Grimm rise and bonds form, the Black Moon must face a choice no duel ever prepared him for:

Remain a perfect weapon,
or become a flawed human.