Amatsuka Keibi Hoshou, Honjitsu mo Trouble Hasseichuu

Ayukawa Minami is a rookie security guard who daily confronts troubles in the downtown area with his senior, Tachibana Kei, whom he admires. Then one day, a thief rampages through a shopping mall. Kei reins in the criminal, who swings around a bottle of sake while running away, with a brilliant backdrop throw. Minami praises his senpai for his excellent work, but Kei himself is not happy about it because he feels overstressed by the violence...

(Source: Junet, translated)

Note: Originally serialized under the title "Amatsuka Keibi Hoshou, Honjitsu mo Trouble Hassei-chuu (天使警備保障、本日もトラブル発生中)".