自傷無色 (Self-Injury Colorless) is a VOCALOID song by Japanese producer sasanomaly (ササノマリイ), originally released on niconico featuring Hatsune Miku. The track later received a human cover by the in-game unit 25-ji, Nightcord de. (25時、ナイトコードで。) from the mobile rhythm game Project Sekai: Colorful Stage! feat. Hatsune Miku, with vocals performed by Kanade Yoisaki (CV: Tomori Kusunoki) and Mafuyu Asahina (CV: Rui Tanabe). This cover version, credited to all three acts together, was brought into maimai でらっくす Splash on January 21, 2021 as part of the ongoing collaboration between the two Sega rhythm-game franchises. The song's lyrics dwell on themes of self-worth, identity, and the desire to be someone else, a characteristic emotional register that aligns closely with the darker, introspective tone of the Project Sekai unit performing it. At 120 BPM, the MASTER chart (designed by はっぴー) sits at level 12+ (constant 12.8), while the EXPERT chart (designed by Jack) holds at level 9. A brief incident during the Splash PLUS update saw unintended changes to the MASTER chart's Slide patterns, which were reverted on April 1, 2021 without affecting note counts or scores. The Asian version of maimai DX received the song later than the Japanese arcade, added with the FESTiVAL edition on February 3, 2023, marking the first time a song's release was delayed in this way for the Asian region, while the Chinese version arrived even later on 舞萌DX 2025 on December 4, 2025.