Kisaragi Ittetsu

Kisaragi Ittetsu is an old mentor/elementary school teacher of Tachibana Sakon. He was the one who convinced Sakon not to throw away his puppet, Ukon, during Sakon's childhood when he was bullied and made fun of for playing with dolls (aka puppets).

He now works for an ancient Egyptian museum as a manager.

He was suspected for the murder of Yuuki Mari, the director of the museum, due to a "dying message" using the director's earring and the fingerprints found on the vents used to drop the keys needed to make a sealed room mystery.

Ittetsu makes a small appearance in the last episode, he appears in the audience to watch Sakon's play.