Aegis in the Dark

Aegis in the Dark (闇のイージス) is a manga series written Nanatsuki Kyoichi and illustrated by Fujiwara Yoshihide. It was serialized in Weekly Young Sunday.

Plot
Karito Tate is a bodyguard who takes on various jobs to protect VIPs using martial arts, various firearms, or high-tech gadgets. He is not allowed to kill, but only to protect with his right arm.