Basically I wrote this song when I was in a happy place. I’m like “where am I getting my inspiration from right now?”, it’s kind of tricky for me to feel… And so, I was kind of sitting, smashing champagne in the session, it came about. And “Bikini porn” to me actually means ‘tan lines’, so it’s the kind of reflecting on living in the sun, and the sort of weird life style in LA that can be so dark and so fun, kind of back and forth.

–Tove Lo via Beats 1

In an interview with Pitchfork, Finneas explained:

I got sent a really simple bare demo of that song, which is definitely just the writing demo, and it was just about really getting that song production wise to a place where everybody was like, “fuck yeah, this is where it needs to be.” There’s a really incessant vocal, sort of like whoop in the song that plays a really big role. The demo I sent had a great lead vocal, but it had no harmonies at all. It was one lead track, and so I had to synthesize all of the other harmonies. I used a plugin called Little AlterBoy to do that and I left it on what’s called Robot Mode where it holds one pitch, and then I automated all of the pitch changes into all of the vocals. And I liked that it sounded robotic. I think if you’re trying to have hyper-realism, you would go about it in a different way. If you have a voice that is in a higher register and you pitch it down, it doesn’t sound like you singing lower. It sounds like this sort of a voice changer. All of every vocal layer that isn’t the lead was artificial in that song.

Obviously, I’ve been a huge fan. I was gonna say “for a long time”, but you know… Obviously, I reach out to everyone I wanna work with. Getting a ‘yes’ from him, you know, he has choices, man. I was very excited and honored, that he wanted to work with me. We wrote this beautiful, kind of, more poetic ballad [(Passion and Pain Taste the Same When I’m Weak)] and I just was like: ‘I love writing with you, you’re bringing out this other side of me, I think, a lot of people try to push more of a happier way.

–Tove Lo via Beats 1