The Plain Salary Man Turned Out to Be a Hero: He Was Invincible, Only to Be Exposed on His Niece's Dungeon Stream - Vol. 1 Ch. 3

[MangaDex]

 

[Churkey]

Is he just like Kira Yoshikage except he got that quirk from that stress guy meshed into one? Oh and of course a better personality than both fused characters.