S1·E6 The Bad Girl

Tamahiko tracks Ryo down to her home, only to discover that she is the oldest of three younger siblings and her theft is due to the fact that her father is an abusive alcoholic. The next day, Tamahiko returns to Ryo's home to try to retrieve the bookmark she stole from him and Ryo agrees to return it if Tamahiko helps her younger siblings with their school homework.