Billie Eilish fans have been left baffled by her sibling bond with brother Finneas O’Connell after he helped her write a song about oral sex.

The What Was I Made For hitmaker, 22, has been working with her brother Finneas, 26, since they were kids. They’ve won numerous accolades – including Oscars and Grammys – for their lyrical prowess. But with the upcoming release of Billie’s new album Hit Me Hard and Soft, they’re taking things to the next level.

Billie was keen to preview one of her new songs while performing at Coachella. The track – reportedly called Lunch – features the lyrics: “I could eat that girl for lunch / Yeah she dances on my tongue / Tastes like she might be the one / And I can never get enough, I could buy her so much stuff, It’s a craving, not a crush.”

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The song goes on: “Call me when you’re there / Said ‘I brought you something rare, and I left it under ‘Claire’ / So now she’s coming up the stairs / So I’m pulling up a chair and I’m putting up my hair.”

Billie Eilish
Billie Eilish fans are baffled by how her brother writes her racy lyrics

It’s pretty clear the song is referencing something a little heavier than simple snogging, after Billie came out as bisexual last year. But fans have been left baffled by the sibling bond between Billie and Finneas after he helped her pen the racy lyrics.

One said: “Okay but how is Finneas sitting there making this, bless him.” While another TikTok user suggested: “He probably just mentally separates it if that makes sense. Like he probably just focuses on the music rather than what the lyrics say/his sister being who sings them.”

Billie Eilish
Billie's new song Lunch appears to be about oral sex

Someone else joked Finneas is “stronger than I’d be”, while another social media user said: “Finneas is so cute. Writing this kind of sh** with your sibling must be quite something! He must have to block out his mind completely like that’s his baby sister!”

Billie calls Finneas her “best friend”, while he told Variety she is “incredibly generous” about sharing the credit with him. He said: “It’s crazy and cool to me that people are so aware of the creative circumstance.”

The pair began attending a songwriting class taught by their mum Maggie Baird when they were just 12 years old, which took songs from the Beatles in order to teach kids about composition. She said: “The class was just an hour for 10 weeks or so, but Finneas was like [Eureka] and in a few months he formed a band.

Billie and Finneas have gone on to bag numerous awards
They debuted the new release at Coachella

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“All I had to teach him was the basics, and he immediately got it – and the same with Billie,” their mum said. Billie shot to fame when she recorded her brother’s track Ocean Eyes in 2015, launching her into stardom and eventually winning them both record deals.

Billie said: “Then we started writing together […] I think the first one was either Hostage or Bellyache.”