The protagonist is not traveling or reborn, but has awakened the ability of "memory retrospection", which can turn back the time of the entire city for seven days. However, after going back, everyone in the new timeline will automatically forget everything about the old timeline, including himself - every time he goes back, the protagonist will randomly lose an important memory in his life as a price. He is not reborn, but trying to piece together the truth while experiencing constant amnesia.
