Electromagnetic Girlfriend

Juu Juuzawa, a loner with no interest in making friends, is annoyed when a girl named Ame Ochibana insists they were connected in a past life. She even declares her desire to serve him, which he dismisses as nonsense. But when a classmate is killed, Juu suspects Ame might be involved and decides to keep an eye on her. To his surprise, her sharp mind and unexpected talents make her a useful ally as they dig deeper into the murder mystery together.