Ōten no mon

• Ja Kanji — 応天の門 • Genre — * Drama • Historical • Suspense

• Type — manga • Author — Yak Haibara • Publisher — Shinchosha • Imprint — Bunch Comics • Magazine — Monthly Comic Bunch • First — October 21, 2013 • Volumes — 21 Ōten no Mon is a Japanese manga series written and illustrated by Yak Haibara. It began serialization in Shinchosha's seinen manga magazine Monthly Comic Bunch in October 2013.

During the era when the Fujiwara clan was gradually seizing real power in the imperial court, rumors were rampant among the nobles of Heian-kyō that maids were disappearing night after night from the Fujiwara clan's residence. The nobles whispered that this was the work of an Oni, and the rumors eventually reached the ears of the Emperor. Ariwara no Narihira, who was in charge of guarding the capital, received an imperial order and began searching for the culprit. However, when his friend Kino Haseo was arrested as the culprit in the maid abduction, Narihira, who wanted to prove his innocence, asked for the cooperation of Sugawara no Michizane, Haseo's classmate whom he encountered at the scene of Haseo's arrest. Together with Michizane, who reluctantly promised to cooperate, they continued the search for the culprit. After finally solving the case of the missing maid at the end of their investigation, Narihira and Michizane continue to uncover the bizarre incidents occurring in Heiankyo one by one, but they gradually become entangled in the power struggle between the Fujiwara and Tomo clans, who are involved in the background of the cases.

Written and illustrated by Yak Haibara, Ōten no Mon began serialization in Shinchosha's seinen manga magazine Monthly Comic Bunch on October 21, 2013. The series' chapters have been compiled into twenty-one tankōbon volumes as of January 2026.

A stage play adaptation featuring Takarazuka Revue performers Kanato Tsukishiro, Mitsuki Umino, and An Hōzuki was held at the Takarazuka Grand Theater from February 4 to March 6, 2023, and the Tokyo Takarazuka Theater from March 25 to April 30 that same year. Another stage play adaptation featuring Ryuji Sato, Katsunori Takahashi, and Mari Hanafusa was held at Meiji-za in December 2024.