Corse Party D2: Depths of Despair
Yui invites some of her former students to a class reunion at Kisaragi Academy's classroom 2-9. She steps out for a moment to speak to Tsukasa after everyone arrives. Noticing that Ayumi seems depressed, Yui suggests telling ghost stories by candlelight in an attempt to cheer her up.
Yui makes a cameo in the Mended Soul ending during the ghost story scene.
Extra Chapter 2
Yui speaks with Tsukasa in the hallway outside of classroom 2-9 during the reunion. She catches up with Tsukasa and receives the updated medication for her cat Monet. At Tsukasa's suggestion she decides to try to cheer up Ayumi by telling ghost stories.