Ghost of Undecimber, known in Japan as 13 Gatsu no Yūrei (Japanese: 13月のゆうれい, Hepburn: Jūsan Gatsu no Yūrei; "The Ghost of the Thirteenth Month"), is a Japanese manga series created by Suzume Takano. Shodensha serialized it in their josei manga magazine Feel Young from January 8, 2015, to December 8, 2016, and released it across two collected tankōbon volumes in 2016–2017. The story follows a love triangle involving Neri, a woman who dislikes being feminine; Kiri, a cross-dressing man; and Suō, an otherwise heterosexual man who finds Kiri attractive. The series was critically well received for its themes of questioning gender roles, and was selected as one of the recommended works at the Japan Media Arts Festival in 2018. Source: Wikipedia (en)