Based on the manga by Musubi Onigiri.

Ookami had her skirt swiped by the rumored "skirt bandit." Her teacher Akagashira happened to be passing by and came to Ookami's rescue. Akagashira took Ookami home, but Ookami had a real reason for bringing Akagashira there... "Stuck with a girl in a room with the lights out, I … can't help myself!"

(Source: Anime News Network)