15 Nengo ni Oretachiha

Akama is reunited with his former prefect Kosuke. The "strongest watchdog" and his "prefect" who were famous in their high school days are now "an asshole who spends all his time fighting" and "a detective who works hard as a single father. Akama takes a liking to Kosuke's young daughter, Kaye, and the three of them live together at his house. While living in a pseudo-family, Akama begins to feel strongly about Kosuke. (-DeepL)