My Wife is a High School Girl

Iwasaki confronts Kyosuke with her suspicions in a family restaurant after school. Flustered, Kyosuke runs off without his briefcase, so Iwasaki delivers it to his house. Asami tries to hide, but is betrayed by a cockroach. Dinner winds up on the floor again. Kyosuke is called to the headmaster's office. Seeing Iwasaki standing at the headmaster's desk, and fearing that he has been discovered, Kyosuke presents the headmaster with the already prepared letter of resignation that he is carrying. Then a Christmas miracle occurs. (Source: Wikipedia)