Brock Lesnar, a.k.a. Judy Blume, discusses his new book on Good Morning America.

Although fans of professional wrestling know Brock Lesnar as a fearsome competitor in the ring, millions of adolescent girls worldwide know him better by his pen name, Judy Blume.

Though Lesnar tries to keep his writing career out of the spotlight, he spent five hours today signing copies of his latest book — a tale of a bullied-but-brave tomboy called Next Big Thing.

Lesnar’s dual life as a professional athlete and author of young-adult fiction comes as a surprise to many fans of both genres, since his imposing in-ring character seems at odds with his ability to tap into the psyche of girls blossoming into womanhood.

What’s especially amazing is that Lesnar, who has been publishing novels since the 1960s and is now 77 years old, still looks so athletic and youthful.

Paul Heyman, Lesnar’s advocate and literary agent, says his client has “the uncanny ability to break your heart or break your back.”

According to Heyman, Lesnar is already working on his next book — a semi-autobiographical coming-of-age tale called Suplex City Dreamin’.