Grisaia no Kajitsu S01E08 - Seed of the World Tree I

Yuuji suddenly announces that he'll be Makina's father. Everyone around gets confused and looks at them skeptically, but the two of them act like father and daughter very dilligently. Yuuji even becomes a rather Spartan father at the end of the term. He attempts to drive all the knowledge he possesses into Makina, from hand-to-hand combat techniques to marksmanship.