Higehiro: After Being Rejected I Shaved And Took In A High School Runaway Vol. 1 (Light Novel)

Yoshida is a 26-year-old salaryman on his way home from a night of drinking after having just been dumped by the girl he has been crushing on for five years when he happens upon a high school girl named Sayu sitting alone under a streetlamp. After finding out that she ran away from home and has nowhere else to go, he lets her stay with him in exchange for doing housework. Thus begins the strange life between a runaway high schooler and a rejected salaryman.
Notice: This book is written in Japanese.