Aito Aoyagi is a Japanese novelist and manga story writer born August 26, 1980, in Chiba Prefecture. He graduated from Waseda University's Faculty of Education, where he belonged to the university quiz research circle, and he worked at a cram school in Chiba City in teaching and teaching-material development before establishing himself as a writer. He debuted in 2009 with the mathematics mystery novel Hamamura Nagisa no Keisan Note, which won the third Kodansha Birth award in the novel category; the series later surpassed six hundred thousand cumulative copies and became a recurring source for his manga work.

In the anime and manga field, Aoyagi is primarily active as a story writer, providing original stories and concepts that other artists draw. His best-known manga credit in this role is Tonegawa Ririka no Lab Story, also known as Tonegawa Ririka no Jikkenshitsu, a science-themed mystery series serialized in Kodansha's Nakayoshi magazine from 2014 with art by Hasegaki Narumi. The story follows a high school girl who dislikes science and receives a flask from Archimedes that summons famous scientists to help solve strange cases. His other verified story credits include the manga adaptation of Hamamura Nagisa no Keisan Note in 2013, the original light novel of the same title in 2009, Houkago Minkowski in 2014 with art by Obiya Dori, the manga Akazukin, Tabi no Tochuu de Shitai to Deau, and Akagamin wa Dasshutsu Dekinai.

Aoyagi frequently adapts or extends his own mystery novels into manga, and his recurring partnerships with specific artists form a notable pattern in his career, including work with Hasegaki Narumi on Tonegawa Ririka no Lab Story and with Tanaka no Ka on the Akazukin manga. His production specialty is mystery plotting built around mathematical, scientific, or fairy-tale motifs, often combining educational concepts with puzzle-driven narratives. His original novel Akazukin, Tabi no Tochuu de Shitai to Deau was also adapted into a Netflix live-action film in 2023, and another novel, Mukashi Mukashi Aru Tokoro ni, Shitai ga Arimashita, was nominated for the Bookseller Award, illustrating the reach of his story work beyond manga.