U-so-tsu-ki★Knight

Touko Momozono is a bright and eager shitamachi girl. She lives with an unwed mother and grandmother, all-female household. Her father had already gone when she was born, but she lived in comfort. Only there was a gaping hole opened in her heart. Recently she has often been an easy target for molsters and thugs, and Kazunari, who is usually boring and one of her colleagues, helps her ride out such a crisis. What is hidden behind his face? Why is she a target for a suspicious-looking man?

(Source: Lovers Dream)