OHTEN NO MON: GATE OF SECRETS

Set in the Heian era, when the Fujiwara clan schemed to seize power at the Imperial Court, a court lady's mysterious disappearance suddenly occurs in the capital. Tasked by the Emperor, who fears it may be the work of the oni, Ariwara no Narihira encounters a young man named Sugawara no Michizane. This unlikely pair - the reclusive student Michizane and the famously charming Narihira, separated by class, birth, and nearly 20 years in age - team up to unravel the bizarre cases in Kyoto! From the rising talent Yak Haibara of "Kaiyu no mori"(Walks in the Woods) and "SP"(Security Police) comes a Heian-period crime suspense manga! (Source: Emaqi) — Description from AniList community (anilist.co).