Elon Musk has a "theory" that Grimes "isn't real".
The 51-year-old billionaire has dated the 'Genesis' singer on and off since 2018 and has two children, son X Æ A-12, two, and 10-month-old daughter Exa with the pop star - whose real name is Claire Boucher - but he said to have told people that he believes he has created a "simulation" to serve as his "perfect companion".
Vanity Fair journalist Devin Gordon claims Grimes shared the theory with him herself.
He explained: "She told me repeatedly that Musk has this theory of her that she’s not real.
"That she’s a simulation who was created by him and exists in his cerebral cortex as sort of the perfect companion to him."
Even more bizarrely, Grimes agrees with the notion.
Gordon added on new documentary series 'The Elon Musk Show': "Which sounds a little crazy and maybe even a little creepy, except, she agrees with it. She said she does feel like this simulation which was perfectly created for him. "According to the reporter, the on/off couple initially bonded over a "scary" thought experiment and share very similar tastes.
He said: "They both made a similar nerdy joke about a scary AI theory of the future called Roko’s Basilisk, which I don’t really even get. And her interests are all the same as his and her music is very technologically oriented."
Grimes and Musk announced last September they had "semi-separated" but the singer later admitted there was "no real word" to describe their relationship.
She previously said: "I would probably refer to him as my boyfriend, but we’re very fluid. We live in separate houses. We’re best friends.
"We see each other all the time… We just have our own thing going on, and I don’t expect other people to understand it."