Billie Eilish's "Bury a Friend" details a strange and slightly horrifying relationship that the singer has with a monster that lurks beneath her bed, who also happens to be her. In its video, you can see her doppelgänger, with soulless holes for eyes, threatening to swallow the singer whole. It's everyone's worst fear: a monster near them when they're at their most vulnerable. And according to Eilish in a new interview with OK! Magazine, it's this fearful, sleep-related thought that inspired the song.

What's worse than a monster under your bed? Not being able to move. You've experienced the uneasy feeling at one point or another and, each time, you just want to hide under the covers. For everyone, it's different. But, often, people see, what they believe, are spirits, demons, or other denizens of the night that can keep you awake, and frozen, until the morning comes.

Eilish elaborated on this feeling in her interview. "I have these terrifying dreams," she told Ok! Magazine, as Uproxx reported. "Sleep paralysis,  night terrors. It's like the whole night is terrifying and then I wake up." She continued on, tying it into "Bury a Friend." "I probably wouldn't have made that song the way it is if I hadn't had sleep paralysis and nightmares."

It turns out, in this case, that sleep paralysis is good. "Bury a Friend" peaked at No. 14 on the Billboard Hot 100 and has been certified platinum. The album it comes from, When We Fall Asleep, Where Do We Go? has not only gone double platinum, but it also won the trophies for Best Pop Vocal Album and Album of the Year at the 2020 Grammy Awards.