Robert Pattinson on Why His Teeth Are Stained in This 2013 Photo with Beyoncé

Robert Pattinson is notoriously tight-lipped about his personal life. Just last month, he revealed that he and FKA Twigs are “kind of” engaged, though he didn’t exactly confirm the news.

But earlier this week, the former Twilight star, who’s busy promoting his latest flick, Good Time, let his guard down for an Ask Me Anything (AMA) interview on Reddit. Some fun facts we learned? His favorite drink is rosé. He’s proud to have acted in Harry Potter and the Goblet of Fire (“It was genuinely a really special experience working on it.”). And he only considers joining social media “in dark moments.”

One curious Reddit user took the Q&A session to a funnier level, however, and brought up a much talked-about 2013 photo of Pattinson, the punk band Death Grips, and Beyoncé. In the photo, the actor looks kind of goofy and has stained teeth.

“How did you meet, how did you end up playing guitar on ‘Birds,’ and what the hell is going on in this picture?” a fan wrote.

Here’s your answer: “Death Grips were one of my favorite bands for years. I played through the walls once in my house on New Year’s Eve and people went from zero to insane so quickly,” he wrote, recounting a party he hosted.

“Then they were randomly sitting next to me in a restaurant a year later eating salad, which kind of surprise me. I started talking to them and they were awesome,” he said. “We initially were gonna do a video together, and then almost started a movie. But through the process became really good friends.”

He explains that Zach Hill, a Death Grips band member, recorded Pattinson playing guitar and voilà, he was featured on the song “Birds.” But what about that picture with Bey, Rob?

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“The photo of us and Beyoncé came from when we went to her concert, drank so much red wine that we all had black teeth, and I was trying to find a place backstage to get all the stuff off my teeth and bumped into Beyoncé, so we took a picture,” he explained.

There you have it.