Scramble★Egg(1982)

Youkei, a 21-year-old college student, just lost his apartment and his roommate as that roommante kicked him out after inviting his girlfriend to move in. So what's a guy to do? Go get stinking drunk and marry the first eligible woman he runs into, an older woman named Keiko, who is as drunk as he is. Next morning, they both wake up not remembering a thing, but Keiko's 14-year-old daughter does - and knows exactly what they did. And she isn't the youngest daughter...