The graduating senior looked unassuming recently as he strummed his guitar on the campus of Harvard University.
But he was no average student, and it was no average song.
Rivers Cuomo, 35, is lead singer of the band Weezer, and he was strumming "Beverly Hills," a recent chart-topping, Grammy-nominated hit.
Six months ago, after completing an 80-city tour in support of his latest platinum album, Cuomo traded in pop hooks for books -- and five-star hotels for a 14-by-9-foot dorm room.
"At first, I was a little nervous about living in dorms," Cuomo said, "because I just thought it might be strange because, A, I'm a celebrity, and B, I'm old."
Cuomo initially enrolled at Harvard in 1995, after the release of Weezer's first multi-platinum album, because he thought he was "wasting his brain." He's been attending off and on for 11 years now between records and tours, and will graduate June 8.
"He acts like any other student," one fellow student said. "He's an incredible humble guy."
"It's pretty cool to live with a legend on your campus," said another.
Cuomo is not your standard-issue rock legend. His songs are often about being lonely or shy, and he's admitted to having bad stage fright on stage -- and at school.
"It's just as terrifying to give an oral presentation to 15 smart kids as it is to sing on 'Letterman,' " Cuomo said. "I think even more so."
He also took a public vow of celibacy out of devotion to Indian meditation, but he's a little embarrassed to talk about it. As he was interviewed by ABC News, Cuomo accidentally knocked out a light with his foot.
"Oops," he said. "I'm sorry."
So when asked about the celibacy thing, he had a ready response: He laughed, and kicked out another light.
Cuomo's vow of celibacy will end when he gets married to his longtime girlfriend 10 days after his graduation.
Cuomo scored nearly straight As at Harvard. Not that he needed to: He's already got a job.
ABC News' Dan Harris and Kathleen Hendry reported this story for "World News Tonight."