無間嫉妬劇場『666』 (read as ネタミニティシアター / Netamini Ti Theater) is a Touhou Project vocal arrangement by the long-running doujin music circle 森羅万象 (Shinra Bansho). The song was added to maimai でらっくす PRiSM on November 8, 2024, as part of the game's ongoing lineup of Touhou-themed tracks. It features the vocalists あやぽんず＊ (Ayapozu) and あよ (Ayo), both frequent collaborators with the circle. The arrangement takes its source material from 「渡る者の途絶えた橋」 (The Bridge of People Who Crossed), the stage 1 theme of Touhou Chireiden ~ Subterranean Animism. The title fuses multiple layers of hellish imagery: 無間 (mukan) refers to the Avici hell of ceaseless suffering in Buddhist cosmology, 嫉妬 (shitto) means jealousy, and the number 666 carries its familiar demonic connotations. The intended reading ネタミニティシアター is a portmanteau, blending ネタミ (netami, jealousy) with a play on "eternity", all wrapped into a theatrical framing. On the charting side, the Master difficulty (level 13, constant 13.0) was designed by Jack and deliberately totals exactly 666 notes across all note types, a thematic callback to the song title that serves as the chart's most immediately recognizable gimmick. The Expert chart was designed by サファ太 (Safata) at level 10.