Meeting Karin Dreijer, AKA Fever Ray, AKA one half of the now-defunct the Knife, is a discombobulating experience. For one, I have no idea what she really looks like; she and her brother Olof sported various masks during their time recalibrating electronic pop as the Knife, while the looks for Fever Ray’s 2009 self-titled debut – a disconcerting, insular song cycle about the loneliness of new motherhood – involved lashings of face paint, a load of dry ice and giant hats that looked like dead animals. In 2010, meanwhile, Dreijer made a rare public appearance, accepting an award for best dance artist at a Swedish awards show while sporting gloopy prosthetics that made it look as if her skin was melting off.

Her face may be on the cover of Fever Ray’s surprise new album Plunge – a pulsating treatise on queer living teased at the end of last month via two clips apparently filmed in a wipe-clean BDSM basement nightclub – but her features are hidden somewhat by the words “Fever” and “Ray” carved into her skin like fleshy cake decoration. So, when we meet outside a subway station in a trendy part of Södermalm, one of Stockholm’s 14 islands, it’s akin to Dorothy pulling back the curtain to reveal the Wizard of Oz is just a human being after all.

Dreijer, a youthful-looking 42, is dressed for Sweden in November (ie she is wearing two coats and her thick black trousers are tucked into robust woollen socks). As I pull out a limp pair of fingerless gloves and button up a coat made for spring in the UK, she mentions she had asked her manager to tell her PR to tell me to bring gloves (“You need wool or leather,” she adds). We chat more about the weather (“This is actually quite warm for this time of year,” she says brightly as the tips of my fingers turn blue), before discussion moves on to Stockholm’s housing crisis; her dislike of London (“I feel like I can’t escape”); the time she went to the Reading festival in 1994 to watch Hole; and how she overcomes Sweden’s winter darkness (lots of Bikram yoga).

What is most surprising, however, is how open she is – on intimate topics such as sexuality and her family life. The Knife rarely gave interviews and when they did they were typically conducted tersely via Skype. Any talk of Dreijer’s personal life was strictly out of bounds during early Fever Ray chats. Today, however, we spend three hours together, the first half of the interview involving a scenic walk around the western edge of the island, up past her old recording studio and near where she lives, the second half sitting in a tiny nook in a (thankfully) warm cafe in nearby Liljeholmen.

The musician’s life has shifted significantly since 2009’s Fever Ray debut, made in the bubble of a nuclear family – Dreijer, her two children and her computer-programmer husband. Throughout Plunge, however, there are mentions of relationships ending, and of new ones starting. Fans have also picked up on the fact she has dropped the Andersson from her surname. “Yes, I got divorced. I was living in a marriage with a man for a long time and for the last five years I haven’t,” she says. On Plunge’s centrepiece, This Country, a throbbing electro stomper with a chorus of “This country makes it hard to fuck”, Dreijer chants “destroy nuclear”, a reference to society’s adherence to the normal 2.4 kids. “This [album] is about freedom, and curiosity. Now I think it’s absolutely possible to create a family that isn’t a nuclear one, but I didn’t know that then. I had lived a very feminist way of life before I had kids and I was shocked at how society treats you when you become a mother. You’re basically supposed to cut your arms and legs off and stay in the house.”

While the last Knife album, 2013’s deeply experimental 80-minute long Shaking the Habitual, was inspired by the duo’s readings in feminist and queer theory, Dreijer says Plunge is less theoretical when it comes to the latter. “I think it’s been more learning by doing this time around,” she laughs. “I’ve been on Tinder. I have had many relations in the last year or so via apps.” How does she define her sexuality now, I ask. “I’m definitely a queer person, but I’m very gender-fluid, I think.” When she’s on Tinder, who is she swiping right for? “I go for the ones that define themselves as women,” she says with a smile.

How to get a head ... a scene from the video for To the Moon and Back. Photograph: YouTube

She says her queerness is something that has developed over time. Born in Gothenburg, she says nobody was gay when she was growing up and that the city, although left-leaning, was “very sexist and homophobic”. In 1994, she started a guitar band called Honey Is Cool, with four male friends, but her presence in the band meant they were regarded as a girl band. “There was one festival that was kind of big in Sweden and we wanted to play but they said their girl band slot was full. It was an extreme situation.” In 1998, she decided to move to Stockholm and started the Knife with her brother Olof, the pair purposefully leaving guitar music behind. “[In Gothenburg] they thought everybody who worked with instruments other than guitars was gay. [My sexuality] developed after I left. Seeing what else was possible.”

One song on the new album in particular – A Part of Us – is about the safe cocoon of queer spaces, specifically nightclubs. “But it’s also about the difference between being inside and then outside,” she says, referring to the line “what we are brings the wrong kind of attention out here”. “You’re always looking back over your shoulder. I have friends who are more masculine-looking women who have been beaten up in Stockholm for not being feminine enough. And yet people still feel very safe here. It’s not like in Tunisia or Iran, which is where many of my friends come from. It’s the death penalty there.”

Patriarchal oppression also filters into the lyrics in relation to society’s attempts at controlling what queer people get up to in the bedroom. “I get very tired of people saying: ‘Oh you’re safe now, you’re equal, you’re allowed to marry’, but I don’t want to marry, I want to fuck!” she says, rattling the table as she leans in. “There’s a lot of fucking on the album – fuck, fuck, fuck the whole time! – but it’s important because the ways of fucking that don’t make up heterosexual sex are super-stigmatised. My kids don’t learn about non-heterosexual sex in school. My youngest came home and was like: ‘Mum, how do girls have sex? Is it like pussy against pussy?’ And I said: ‘Yeah, you can do that’, and that was it. All good. It’s a key thing for human nature to know how to experience pleasure.”

Electric dreams ... Dreijer performs in Rotterdam in 2009. Photograph: Rob Verhorst/Redferns

She’s on a roll now, the most animated she’s been. “Up until recently there wasn’t a Swedish word for the female sex organ for kids to use. There was one for the vagina, but that’s too medical. So when I was younger, I didn’t know how to talk about this [she points between her legs].” Is there one now? “Yes, snippa! But before that there was nothing. There’s a lot on the album about shame, but some of it is about the shame that comes from just being a woman.”

Dreijer also talks about people’s perceptions of her; how she thinks that when people meet her, they expect she’ll be caked in fake blood or, like in one of the Plunge teaser videos, absent-mindedly toying with a metal speculum. “I can feel that when I meet up with people,” she says carefully. “It’s like: ‘Are they going to keep up the illusion or not? Are they going to play along with your fantasy?’”

For Dreijer, Fever Ray is a solo project but hidden behind a character, or multiple characters, that appear in the videos and on stage, almost as a defence mechanism. Asked why she doesn’t release solo material under her own name, she says she can’t: “I want to keep a distance between my private life and my work.” (Later, she can’t contain her glee at the fact none of the other parents recognise her at the school gates.) While Fever Ray, the album, was influenced by very real experiences – particularly the boredom of new motherhood (she has two daughters, aged 10 and 14) – the sense of feeling disconnected from the outside world was communicated more by the album’s eerily claustrophobic sonic landscape and lashings of pitch-shifted vocal effects.

Cutting edge ... Dreijer as one half of the Knife. Photograph: Elin Berge

On Plunge, however, the music is more manic, the lyrics more outward-looking and direct (lead single To the Moon and Back closes with the line “I want to run my fingers up your pussy”), while the vocals sit higher in the mix. Even the title suggests new beginnings and freedom. “Yes, throwing yourself into something,” she says, forking a mouthful of chocolate cake into her mouth. “Being brave and being open to do that. It’s about taking back what’s me.”

Having cleared out the cafe, we talk about To the Moon and Back. It’s about “the excitement of going out”. In its video, we witness the old Fever Ray character from the first album being shorn of her blond hair in favour of a bald head (actually a skull cap). “Yeah, it’s like when Britney Spears shaved off her hair that time,” she says, referring to Spear’s infamous haircut from 2007. “I love that idea of shaving your head and starting a new beginning.” For Dreijer’s character in the video, however, that new beginning involves being tied up and urinated on during a wonderfully perverted tea party. “I was like: ‘What is the nicest role play?’” she says, ignoring my arched eyebrow. “There’s so much BDSM role play in videos and it’s super violent, so I wanted to have a role play that was fun. I said: ‘Let’s have a tea party and I want to be the table.’”

I raise the point that one of the characters then urinates on her. “It’s a nice tea party,” she maintains. “I think sex, role play and games don’t have to be violent, they can be cute.” It’s interesting that the character who does all the weeing in the video, the same one present throughout her campaign, is wearing a muscular body suit. What does it represent? “I think it’s somebody who wants to be loved and to fit in,” she says. “They want people to look at them, and have a nice body with it. But it’s a costume, which is important; it’s soft.”

As our time comes to an end, we chat about her youngest daughter’s obsession with the lip-sync app Musical.ly (“I’m just trying to work out who she’s friends with on it so that it’s not scary people”); her retirement plans (“Maybe I’ll become a florist, or captain a boat”); and my regret at missing that weekend’s Plunge launch party. “It’s in a gay sauna,” she chimes. “There’s a magician!” Inevitably, given all the chat about power structures and female bodies, talk turns to Weinstein and Trump. It feels as if, as a society in general, we’re talking more openly about this huge power imbalance, I say. “Yes, it’s talked about but I wonder what will come out of it,” she counters. “[Weinstein] will keep his money and money is power. You have to take their money; that’s how we change power. Revolution.”

When is that happening? “Maybe 10 years.” She senses my surprise at the time scale. “It’s happening. We just have to take it all back and start again.”

Plunge is out now on Rabid