灰原くんの強くて青春ニューゲーム

College student Natsuki Haibara has a stable future lined up, yet he keeps replaying the high school years he spent socially anxious and overweight, when every attempt to become outgoing fell flat. After praying for a do-over, he wakes up seven years in the past, one month before the entrance ceremony, and uses that month to get in shape. This time his first impression lands, he makes friends, and he falls all over again for his old crush Hikari Hoshimiya, making dating her his new goal, with a workout regimen, online how-to guides and a childhood friend backing his second run.