TUMENECO
The Secret Door (ヒミツのトビラ, himitsu no tobira)

Compilation CD-BOOK: Touhou Tamatebako (Compilation CD-BOOK 東方 玉手箱) by Melonbooks Records – Track 5, disc 1
Released 2020-05-02
Website

Arrangement: tomoya
Vocals & lyrics: yukina
Based on Merry, the Magician (魔術師メリー) from Rendaino Yakou – Ghostly Field Club (蓮台野夜行　～ Ghostly Field Club).