Soushoku Joushi No Otoshikata Manga

草食上司のオトしかた ; How to Seduce a Herbivorous Superior ; Soushoku Jyoushi no Otoshikata

From Shinmakoku Scanlations : Ever since Nakayama was taught about work by his capable superior Asaka, he has fallen madly in love with him. He's been chasing him until he gets into the same office. However, Asaka has become a strict, cold and violent superior...! So Nakayama begins his days of getting beaten up...!! (Even though that's quite a turn-on in its on way!) But actually, Asaka has a certain secret that makes him afraid to fall in love...