I'm Standing on a Million Lives 15 (manga)

Yusuke Yotsuya doesn't care about getting into high school-he just wants to get back home to his game and away from other people. But when he suddenly finds himself in a real-life fantasy game alongside his two gorgeous classmates, he discovers a new world of possibility and excitement. Despite a rough start, Yusuke and his friend fight to level up and clear the challenges set before them by a mysterious figure from the future, but before long, they find that they're not just battling for their own lives, but for the lives of millions...