The Revenge of My Youth Volume 1

Shin' ichiro Niihama works at a job he hates, for a company with no morals, under a boss who detests him. After years of corporate abuse, one day he collapses. He wakes, only to find- he's returned to his high school self. Reunited with his once lost mother, Shin' ichiro realizes he's leapt back in time. Given a second chance at high school, he vows to do things right this time.