Yata-Momo, Part 1 (manga)

Good-for-nothing himbo Momo lacks the ability to look after himself, while Yata is a reliable but simple lug. The two get off to the worst possible start when Yata comes across Momo during a post-sex clean-up in a public restroom. Taking advantage of Yata's kindness, Momo ends up staying at his apartment.

As he spends more time with Yata, the once-slovenly Momo starts to change... But in the midst of this, Momo's previous "owner" shows up.