Mahiru Umino, a 24-year-old office worker, possesses a unique ability to see people's past lives. However, the trauma of her own past as a seal, who was tragically killed by a polar bear, continually haunts her.
When a new co-worker, Ritsu Kitamura, joins the office, he quickly becomes popular. Yet, Mahiru's fear of polar bears is triggered by the sight of his past self as her mortal enemy. Despite Ritsu's harmless behavior, Mahiru remains cautious, believing that his true nature as a ruthless predator will eventually reveal itself.
As the office is filled with diverse reincarnations, including "Demon King" Nobunaga Oda and a raccoon dog, Mahiru and Ritsu engage in a spontaneous game of cat and mouse.
