Infantoon Fantasy is an instrumental original composition by t+pazolite (Tomoyuki Hamada), a prolific producer known for his high-energy electronic and hardcore tracks across the rhythm-game ecosystem. The song first appeared in CHUNITHM before crossing over into maimai PiNK PLUS on July 28, 2016, where it was placed under the ONGEKI & CHUNITHM genre category. At 185 BPM, it delivers a brisk, driving electronic arrangement with no vocal track, a purely instrumental piece that lets the synth melodies and percussive momentum carry the energy. The portmanteau title blends "infant" (幼児) and "toon" (漫画/卡通) to evoke a playful, cartoonish fantasy mood, a sensibility reflected in the jacket art featuring the character NEO. Over its lifecycle in maimai, the chart levels have been recalibrated multiple times: the MASTER difficulty began as Lv11+ in PiNK PLUS and was gradually raised to its current Lv13+ (constant 13.8) as the overall difficulty curve of the game shifted. An extended cut, Infantoon Fantasy (Uncut Edition), appears on t+pazolite's album Good Evening, HOLLOWood.