RS Project emerged victorious in the MechaTsuku competition hosted by Every Star's mobile novel enterprise. Their winning entry unfolds in a parallel universe akin to present-day Japan, beleaguered by assaults from alien entities dubbed "Kikou" (Trick) who arrived on earth a decade back. The pilot, Mizuru Mido, and her assistant, Fuu Sagami, take center stage as they maneuver a mecha fabricated from the remnants of their arch foe. However, Mizuru's involvement in the skirmishes results in amnesia, prompting the duo to embark on a quest to find a remedy for the predicament.