Marc Rebillet was building a song. At the first of two back-to-back sold-out shows at the Boom Room in Fishtown, the crowd listened as he began that new track.

“I said, ‘Baby!’ ” he crooned into the microphone a cappella, “ ‘There’s something you got to know!’ ”

He sang with the confidence of a leader of a R&B quartet, wailing as he ad-libbed.

“Sing it, Marc!” one man shouted. “Preach, baby!” shouted another.

“Something that I got to tell you,” Rebillet continued soulfully. He coughed, seemed to clear his voice, then tried the lyric another way. “I said, it’s something that I got to tell you.”

Rebillet made a loop while singing the line, starting with a deeper baritone version, then lifting the notes higher, quickly layering the parts into a harmony. Then he added drums. The vocal had the feel of urgently delivered ballad; the beat, though, was an up-tempo knock. The crowd celebrated. This was a dance song now.

He filled out the song, improvising additional instrumentation on his keyboard, a trademark of Rebillet’s style. The “something,” of course, was merely a preface. He was ready for the moment of sharing.

“Ayo,” he sang, “my penis width is weird.”

Rebillet composes comedy music. His improvised loops regularly make for funky, enjoyable beats; his lyrics are regularly absurd. He’s a classically trained pianist and former actor, both evident in his performances. Rebillet, who hails from Dallas, but is currently based in New York, gained popularity through YouTube and Facebook, where he posts new tracks. His rap voice is almost akin to “Weird Al” Yankovic, but his live looping technique reminds of British singer-producer James Blake. In interviews, he has pointed to the comedian-musician Reggie Watts as a source of inspiration.

Before the internet buzz, Rebillet worked as a waiter, customer service rep, and executive assistant (among other gigs) as he sought to gain traction with his music. He’s produced non-comedic music, but has been shooting for laughs over the last few years. Rebillet’s YouTube channel now has approximately 126,000 subscribers. His Facebook has roughly 625,000 followers. Naturally, his work is popular for memes.

In an email, Rebillet said of his process: “There are no considerations, haha! I sit in front of my setup and play around until I find something I like, and then I come up with some idea to give it a theme. There’s no planning or thought aside from: ‘I dig this.’ ”

The Texan does not perform with a straight face. Rather than a head bob, he did more of a rhythmic head swivel, as he continued to sing his, um, confessional.

“Gotta tell you, baby, so you’re not surprised!” he sang.

A fan threw something that Rebillet didn’t immediately recognize.

“What was that?” he asked, as the loop kept playing. He picked it up. It was lavender-colored lace panties. Rebillet put them on his head. Back to the song.

The crowd ate it up as Rebillet both sang and rapped. Rebillet, who is white, rhymes and sometimes addresses his audience with the markers of black speech.

“Just a little bit of water is what we drinking tonight,” he told the crowd between songs.

While some comedians have been criticized for using black accents, Rebillet’s videos are somewhat popular on black Twitter.

Rebillet performs at the Boom Room in Fishtown Friday, December 21, 2018. MARGO REED / Staff Photographer
Rebillet performs at the Boom Room in Fishtown Friday, December 21, 2018. MARGO REED / Staff Photographer

The venue live-streamed the set, as Rebillet traveled through several genres of black music, as his lyrics hit on topics like craving espresso, wiping windows from a scaffold with “industrial Windex,” and desires to be intimate with his data. Rebillet’s oddball freestyle often takes the form of storytelling.

“I’m at the Copacabana in 1945,” he rapped, before noting, “War is over, baby.”

He went on, setting the scene: “I’ve got my salmon, I got my martini, I got my confidence.”

Kensington-based DJ and producer tiedye ky was there after scoring a gifted ticket. He hadn’t been familiar with the YouTuber, but the show made him a fan.

“[He’s] super different and experimental,” said the DJ. “I love the risks that he takes as a performer.”

Concertgoers pointed to Rebillet’s creativity and disarming mix of talents to explain what drew them in.

Kamille Kochico, of Camden, said he doesn’t seem to be as concerned with having a perfectly presented image, as many artists appear to be. She likes that. “He’s like a regular person,” she observed.

“It’s great show you can get down to,” said Janelle Henry, of Manayunk. “But it’s also a comedy set. It’s the best of both worlds.”

Henry admitted that she threw the panties. She had purchased them last year in a Victoria’s Secret after-Christmas sale, and selected them, she said, because you can’t just throw any old pair up there. The show at the Boom Room was the second time she’d seen Rebillet this month. She traveled to New York a couple weeks ago to watch him perform there.

“This girl in Brooklyn threw her leopard thong and he wore it on his head,” she recalled, explaining. “We have to keep the tradition going.”

Rebillet is thinking about returning to non-comedic music in the future.

“A fun idea I’ve had for another kind of live performance would be making improvised beats for rappers on stage and letting them spit over them,” Rebillet told the Inquirer and Daily News. “Outside of that, I’m looking forward to being able to take a few months off and compose a full album.”

Rebillet ended his set by complimenting the audience for their energy.

“I will see you very soon,” he said. “I’m definitely coming back.”