The Agent K-23-15-8 is an agent for Intelligence Agency General Headquarters.
On some earlier point of his life he became an agent for the IAGH.
It would seem that the agent investigated the disappearance Karl von Toten for the IAGH, and found some connection with him being in the conference organized by Isaac Newton in 1886 and some group in the present.
He found the culprits and followed them to the Zurich Hauptbibliothek, but was captured and hasn't been heard of since. Before this, he left a vital clue between one of the book he had borrowed from the library. Probably he was captured by Manfred, same as Kara. We meet a guard who is undercover. Maybe he is K-23-15-8 but that is just speculation.
Apperance and abilitiesEdit
As an agent of the IAGH, he probably had some fighting experience. It would appear that he liked reading biographies, as there was an autobiography of Mata Hari in room 13 and he has at least glanced at Newton's biography.