Infinite Time Travel Harem System

If there is a medicine called "regret medicine" in the world, I really hope that I can go back to college, graduate, and then live and work in peace and contentment and live a happy life. Unfortunately, people cannot be resurrected after death. However, at the last moment of his life, a strange voice sounded... This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.