Q.E.D.

Q.E.D. is a Japanese manga series written and illustrated by Motohiro Katou. It was serialized in Kodansha's shōnen manga magazines Magazine Great and Monthly Shōnen Magazine+ from July 1997 to February 2014, with its chapters collected in 50 tankōbon volumes. The series follows Sou Touma, a university graduate who encounters a variety of investigative cases after returning to Japan from the US. He works with his friend, Kana Mizuhara, combining his deductive skills with Mizuhara's social gifts.

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