In a futuristic Kyoto of 2027, two classmates, the shy Naomi Katagaki and the blunt Ruri Ichigyou, navigate their complex relationship. After witnessing a fleeting crimson aurora, Naomi encounters a time-traveling version of himself from a decade ahead, warning of a tragedy befalling Ruri. Motivated to alter destiny, Naomi embarks on a mission to rewrite their intertwined fate by overcoming his fears and bridging the gap with Ruri. Can his actions defy the predestined path and rewrite their shared future?