A Properly Scheduled Classroom Visit is the sixteenth chapter of Hinamatsuri manga series.
Plot[]
When Hina next attends school, she learns that her class will host an observation day and that she needs to write a letter for Nitta. While initially reluctant to attend, Nitta realizes how much it meant to Hina when he called her his daughter in front of his family and decides to go. However, when he tells his boss about the event, he's so shocked by Nitta's lackadaisical attitude that he has to go to the hospital. As a favor to Nitta, Utako attends observation day and the classroom assumes that Utako and Nitta are married. The chapter ends with Nitta arriving late and Utako declaring to the entire school that she's not Nitta's wife.