A booklet packaged with Harta volume 17 at select stores. It's an anthology of one-shots centering on the theme of beautiful boy. (Source: Natalie, translated)

The plot is divided into two eras, the modern era and the Heian Era. Under the blessing of an entity known as Karura, twin sisters Maiko and Shouko investigate supernatural cases and fight against ghosts and demons using the powers of the Holy Book and the Earth Book. They usually receive help from their known colleagues, such as exorcist Yami no Shiguruto.

Treasure Hunters - Adventurers who search for buried treasure scattered around the world. In Shinjuku, Tokyo, a young man appears as a transfer student at Kamiyoshi Academy. While he seems like a normal student, he is actually a treasure hunter. His mission is to discover a mysterious ruin hidden deep beneath the school. Accompanied by his new friends from school, he sets out to discover the mysteries of a super ancient civilization. However, numerous traps, monsters called "Kehito" that lurk within the ruins, and the clutches of the "student council" stand in his way! (Source: Arc System Works)

Adaptation of the eponymous TV show, that ran on OTV between 1958 and 1960.