Looking for manga

I’m looking for a manga that’s yaoi. Since I only remember the story hopefully someone can name the title.

A boy with blond hair of small stature is paying back his cousins debt with his body to a tall man with dark hair. Said man didn’t let him go out or leave the room (i believe). An important part is the same blond haired boy once gave that man an umbrella when he was sitting on the ground in an alleyway.

Hopefully my description of it helps. The manga had a lot of chapters/volume.