 If you liked
Black Torch
|
 ...then you might like
Jujutsu Kaisen
|
both MC encountered a strong supernatural being that fused with them with unexpected reason and gained strong ability that the enemy was after and they both joined this supernatural agency that will help them trained but also to keep them monitor..
-have monsters looking as enemy
-have agency and nakame they teamed up with
-have shinobi feel
overall same story different setting..