Jubiwa (S01E05)

During the ruckus as the Kaginoji house, Nasa and Tsukasa pledge their love to each other at a church. After Nasa reports to Kaname that he has finally proposed, she points that he still doesn't have a ring. Although he doesn't take much notice at first, Nasa gradually becomes more self-consciousness about the role of a ring in newlywed life. (Crunchyroll)