In/Spectre (虚構推理), also known as Invented Inference in Japan, is a 2011 Japanese novel published by Kodansha and written by Kyo Shirodaira with illustrations by Hiro Kyohara. In 2019 it was republished with illustrations by Chasiba Katase as part of a series. A manga adaptation with art by Katase has been serialized since April 2015 in Kodansha's manga magazine Shōnen Magazine R and since December 2019, also in Monthly Shōnen Magazine. It has been collected in twenty-four volumes. The manga is published in North America by Kodansha Comics. An anime television series adaptation produced by Brain's Base aired between January and March 2020, with the second season aired between January and March 2023.
Plot
While struggling to get past a break-up with his girlfriend, Kuro Sakuragawa was approached by Kotoko Iwanaga, a girl who declared that she has been in love with Kuro since she met him two years ago. She then tells him that she is a sort of Goddess of Wisdom where she serves as the intermediary between the real world and the supernatural world. Kuro, of course, doubts her at first but after fighting a in a library and revealing to each other their true identities (Kuro is actually a monster due to having eaten two different flesh, giving him the powers of immortality and near-absolute precognition), Kuro agrees to help Kotoko on her various adventures as the peace-keeping Goddess of Wisdom.