Tsuyoshi

• Name — Tsuyoshi: Daremo Katenai, Aitsu ni wa • Ja Kanji — TSUYOSHI 誰も勝てない、アイツには • Genre — Martial arts

• Type — manga • Author — Kyōsuke Maruyama • Publisher — * Cygames • Shogakukan • Imprint — Ura Shōnen Sunday Comics • Magazine — Cycomi • First — November 29, 2018 • Volumes — 31 Tsuyoshi: Daremo Katenai, Aitsu ni wa is a Japanese manga series written and illustrated by Kyōsuke Maruyama. It began serialization on Cygames' Cycomi manga website and app in November 2018.

Hoshizaki Ainosuke is the winner of the All Japan University Karate Championship, but is disappointed when he learns that his rival Yumeoka Teru did not defend the championship title - and that he had given up karate altogether after meeting Kawabata Tsuyoshi, an impossibly strong fighter who appears to be a scrawny 24-hour convenience store worker. As word spreads about Tsuyoshi, who is constantly fending off challengers who come to his store to fight him, secret martial arts agencies from Russia, China and Japan work to try to recruit him to their ranks, and Ainosuke and Teru inevitably get involved trying to support Tsuyoshi against various agencies who have their own designs for him.

Written and illustrated by Kyōsuke Maruyama, Tsuyoshi: Daremo Katenai, Aitsu ni wa began serialization on Cygames' Cycomi manga website and app on November 29, 2018. Its chapters have been compiled by Shogakukan into thirty-one tankōbon volumes as of July 2026.

The series had a collaboration with kickboxer Tenshin Nasukawa in August 2019.

The series had over 5 million copies in circulation by January 2025.