Akari Tokitou is a cheerful, easygoing girl who's probably best known for her unwavering devotion to Menou—she's constantly trying to protect her, even when Menou has her own agenda. When Akari got pulled into Menou's world, she was assigned the Pure Concept of Time, a power that makes her essentially unkillable, though she rarely seems to realize just how broken that ability is.
Before all this, Akari had a pretty lonely existence back in Japan, which explains why she's so eager to embrace this new world and everything in it. She genuinely believes meeting Menou was fate.
The thing is, Menou is actually trying to find a way to kill her—and Akari's usually clueless about it. But when things get dire, her memories from previous time loops suddenly come flooding back, and she becomes way more capable with her powers. Without those memories, though, she's honestly pretty helpless in a fight and has to lean entirely on her Concept ability to survive.
Akari's goal is oddly specific: she wants Menou to be the one to kill her, all while keeping Menou alive herself. After each crisis passes, she uses Regression: Memories, Soul and Spirit to wipe her own knowledge of the time loops clean, resetting her back to her usual oblivious, happy self.
Content compiled by AnimeList.moe from publicly available sources.