Michiru Saiki was Arata Kaizaki's superior from his former company.
Saiki had long brown hair, which was generally put into a ponytail.
Saiki supported Kaizaki as a newbie employee but due to constant harassment from their coworkers, she was driven to commit suicide which led Kaizaki to quit the company after working for only 3 months after employment.
Arata Kaizaki - Michiru was Kaizaki's Senpai and major supporter throughout his time in the same company. He described her as bright and cheerful person. At the time in the company, she was pressured and harassed by coworkers which led to her suicide. Kaizaki never really recovered from the incident and was unable to move on until the ReLIFE project. Kaizaki was finally able to move on after visiting her grave and send his thanks for her guidance, and apology for being unable to support her.
'Grow up Kaizaki'