That Guy And I, Aitsu to watashi, あいつと私 (1961) dir. Kō Nakahira

Asada Keiko and Kurokawa Saburo are two young college students. When Keiko visits Saburos house, she meets his father Kokichi and his mother Motoko. Motoko is a famous hair dresser, who openly flaunts her lover. When Kokichi and Motoko fight, which they do a lot, he routinely threatens to leave but never quite does. A relationship develops between Saburo and Keiko, but Saburo is shaken when his mother tells Keiko the truth about Saburos past and the secret of his birth.