naraku within is an instrumental track composed and arranged by Kenji Fujisawa (藤澤健至) under his Team-MAX alias for the Ninja Slayer (ニンジャスレイヤー) multimedia franchise. Originally serving as background music in official Ninja Slayer promotional videos and audio dramas, the track was brought into the maimai arcade series as part of maimai ORANGE on December 4, 2014. The song operates at a steady 130 BPM with no vocal track, relying on its driving electronic-industrial arrangement and gritty synthesized textures to evoke the cyberpunk ninja dystopia of its source material. Its time in the maimai catalog was relatively brief, it was removed from the arcade rotation on December 14, 2017, placing it among the earlier wave of delisted songs in the series. An alternate arrangement, titled ナラク・ウィズイン・フロム・アニメイシヨン (naraku within from Animation), was later produced for the Ninja Slayer from Animation anime adaptation. The Master chart, clocking in at Lv11+ (constant 11.6), was designed by ロシェ@ペンギン, while the Expert chart (Lv9) was handled by Jack.