The man behind a viral meme that transcended sneaker culture has passed away.

According to numerous reports, Brandon Moore (aka Young Busco), died in his sleep Sunday morning. The 31-year-old rose to internet prominence in 2015 after uploading his unforgettable "What are those?" clip to Instagram. Shortly thereafter, Moore's video gained ground on Vine, where it's since racked up nearly 38 million views.

It didn't take long for the phrase to move from sneaker to pop culture, showing up in countless re-creations and being mimicked by the likes of Saturday Night Live, Black Panther, and even Michael Jordan.

Despite the video's viral success, Moore expressed regret for failing to properly capitalize on the fame by copyrighting the saying, telling Huffington Post earlier this year that the situation left him depressed.

Moore, an aspiring comedian and social media personality, lived in Oakland, California, and is said to have been a father of five, although some outlets are reporting he had nine children.

A cause of death has not been revealed.