Rashid Umar Abbasi/Reuters; Neilson Barnard/Getty; Melia Robinson/Business InsiderElon Musk and Grimes.

• Grimes wore a choker necklace that they reportedly designed together, which people think looks like the Tesla logo.

Elon Musk and musical artist Grimes made their rumored relationship at least red-carpet official on Monday night, when the couple stepped out at the 2018 Met Gala together.

Grimes, 30, appeared to be wearing a choker inspired by the Tesla logo.

Charles Sykes/AP

Here's the Tesla logo, for comparison:

REUTERS/Robert Galbraith

US Weekly is reporting that the couple designed Grimes' dress together over a dinner date and commissioned a team to create the futuristic ensemble. Musk wore a white tuxedo jacket and a collarless shirt.

Earlier on Monday, Page Six reported that Musk and Grimes have been "quietly dating," according to an unnamed source. The gossip site said the pair met online about a month ago, after Musk saw on a joke about artificial intelligence that Grimes made on Twitter and reached out.

The pair have not publicly confirmed their relationship.

Twitter saw the "Tesla choker" and expressed their shock:

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