The Hitman Stans 01 (Manga)

The one and only legendary "killing machine" Owaru Endou is the strongest hitman around - until he announces his retirement out of the blue! The whole underworld is stupefied, especially since the reason he's stepping down is to fully devote himself to stanning his favourite idol! Trading guns for glowsticks, Owaru is ready embrace the superfan life! Or he would be if his past could just stay buried, thank you very much...