D.R.A.M. is rolling a joint and singing show tunes. “The hills are aliiiiiive, with the sound of music,” he trills, letting a touch of vibrato stroke the final note into a purr. His trademark smile, a toothy, contagious affair that crinkles his eyes, almost takes over his face. It feels like a hug.

“Oh, the melody, the robustness!” he says excitedly. “They had unmatched riffs. They make it work in the grandest way. It just fills me up.”

It’s not every day a rapper breaks out into a selection from one of his “go-to” musicals (The Sound of Music, if your musical theater knowledge is rusty). But D.R.A.M.’s rhapsody barely elicits a glance from his friends and team members gathered in a Burbank green room on this Tuesday afternoon for the 28-year-old rapper’s late night television debut on Conan. After all, this is a man of contrasts. He two-stepped onto the scene in 2014 with “Cha Cha,” a jokey song built on a Super Mario sample, but his name is an acronym for “Does Real Ass Music.” He pads around with a perma-smile plastered on his face; he coined the phrase “trappy-go-lucky” to describe his sound. Yet he is assiduous with his career and his music, taking great pains to be punctual and fretting over reviews of his debut studio album on Atlantic Records, Big Baby D.R.A.M.—which is in and of itself a rainbow of genres. Of course he loves show tunes.

“Parliament Funkadelic, my biggest influence, has a song, ‘Who Says a Funk Band Can’t Play Rock?’ Why you feel you gotta be pigeonholed to not explore different ways to skin that cat?” he asks. “Skin that cat!”