"The Forgetful Detective") is a Japanese mystery novel series written by Nisio Isin and illustrated by Vofan.

A Japanese drama adaptation also titled Okitegami Kyōko no Bibōroku aired for 10 episodes on NTV from October to December 2015.

The first section is a longer story in which a young man named Yakusuke Kakushidate, who has been falsely accused, plays the role of the sidekick.

[5] He noted that many of his recent works at the time had become more elaborate in terms of rhetoric and dialogue, and therefore he wrote this series with less emphasis on those areas.

[6] Nisio revealed in the afterword of Okitegami Kyōko no Kansatsu-hyō that he has planned a total of 24 volumes for the series.