Fly Me to the Moon manga volume 27 features story and art by Kenjiro Hata.

The exam battle is heating up, along with the romantic tension between Asimo and Himari, and you know what that means - time to swerve into an unrelated flashback! See what happened long ago between Tsukasa and a monk determined to discover the key to immortality. Shake your head ruefully at Tsukasa's chronic habit of exposing her secret to troublesome kids in need of rescue. And find out what all this has to do with Himari, who knows a little too much about Tsukasa. Wait a minute - this flashback isn't unrelated at all! It's thematically connected lore!