Higehiro: After Being Rejected, I Shaved and Took in a High School Runaway, Vol. 3 (light novel)

"Yoshida was just rejected by his crush of 5 years. On the way home from drowning his sorrows, he runs into a girl crouching in the middle of the road, and she offers him a deal--let her crash at his place and he can do whatever he wants with her. When he refuses, she asks to stay for free. This is the story of Yoshida, a 26-year-old office worker, and Sayu, a runaway high school girl, and their unconventional life together"--