Genesis Breyer P-Orridge is laughing.

Sitting in the New York apartment now called home on one of the hottest days of the year, for the artist once decried in the Houses of Parliament alongside others participating in a 1976 exhibition at the Institute of Contemporary Arts called Prostitution as "wreckers of civilisation", it's a laugh that's justified.

The man who gifted Breyer P-Orridge and fellow members of nascent industrial band Throbbing Gristle such a damning soubriquet, after all, was Scottish Conservative MP, the late Sir Nicholas Fairbairn. The flamboyant sexual libertine, former Chair of the Traverse Theatre and ex-member of the Edinburgh Festival Council's name has been mentioned in reports highlighting the ongoing VIP paedophilia scandal and was just yesterday accused of raping a QC's four-year-old daughter. Breyer P-Orridge feels vindicated.

"Why were they so angry at us researching sex magick and other forms of sexuality?" ponders Breyer P-Orridge, who was effectively exiled from the UK in 1992 after the Obscene Publications Squad raided s/his Brighton home following falsified claims of ritual abuse, "when behind closed doors they're the most depraved of all? Establishment techniques of control have always been there throughout history, but they're about to be exposed, just as we tried to expose them back then."

Breyer P-Orridge is talking prior to Edinburgh Art Festival's European premiere of major works from The Pandrogyne Project, an ongoing series of body modifications conducted with Breyer P-Orridge's late wife, Lady Jaye Breyer P-Orridge, in a bid to become matching, non-gender specific beings. This began with the pair getting matching breast implants on Valentine's Day 2003, with Breyer P-Orridge continuing the process since Lady Jaye's passing in 2007.

With Breyer P-Orridge now referred to with s/he, h/er and h/erself pronouns, Life As A Cheap Suitcase (Pandrogeny and A Search For A Unified Identity) charts what has become a life's work, with large-scale images of the artists' ever-changing bodies taking in religious iconography and a Renaissance quest for divine perfection beyond accepted social constructs.

"We live in a society that's based on violence and war," Breyer P-Orridge says, "but what really matters is how you relate to other people. We should be being kind and compassionate, and discussing how we can be better people.

"That's why Buddhism is so appealing. It's time for radical change, and the best way for people to make that happen is not by being dogmatic, but to root themselves in spiritual ways and unconditional love.

"In a way what we've done is very traditional, but it comes at things from a different angle. But we've never wanted to shock. We only ever wanted to seduce. That is the glue that holds everything together, romantic love, and the fear that you might never meet that perfect other half. But we were blessed."

Breyer P-Orridge was last in Scotland for a date with a briefly reactivated Throbbing Gristle at Tramway in 2009. S/he was first brought to Edinburgh by Richard Demarco in 1973, when COUM Transmissions performed their Duchamp-inspired Art Vandals piece, in which guests were engaged in odd conversations as the performers spilt food on the floor. A more conventional solo musical performance, at which Breyer P-Orridge sang over backing tracks, took place at the city's Cafe Royal upstairs - now the Voodoo Rooms - in 2000.

These days, Breyer P-Orridge is in danger of becoming an institution. S/he was recently approached by a Paris-based fashion designer with a view to them working together, and s/he has just been given an award by Rhode Island School of Design for services to art.

"We're being taken seriously at last," Breyer P-Orridge shrieks, "but we're not establishment. Brion Gyson told me a long time ago not to even think about being accepted until you're old. Derek Jarman said much the same thing to me. Unless you're old or dying, no-one's interested."

Breyer P-Orridge's all-consuming relationship between life and art comes from early exposure to the Dadaists and Surrealists.

Now aged 64, the Manchester-born artist christened Neil Andrew Megson has far from finished h/er artistic quest. A film, The Ballad of Genesis and Lady Jaye, was made in 2011, and Breyer P-Orridge is working on a second book based on the Pandrogyne Project. S/he is also working on another film, The Bight of the Twin, in which s/he explores Vodun, or Voodoo, in Benin, West Africa.

For all Breyer P-Orridge's energy about other projects and bruised, but defiantly unbowed loathing for the establishment, everything comes back to Lady Jaye. What this and the Pandrogyny works highlight most of all beyond any notions of grieving is that everything Breyer P-Orridge has ever done has been about love.

"We talk to her every day," says Breyer P-Orridge. "In the film, Lady Jaye was asked how she wanted to be remembered, and she said 'as a great love affair', and that's still happening. She still infiltrates the work. Wherever we go, we meet all these people, and they always say 'We wish we could've met Lady Jaye, she sounds wonderful'. She was. And she still is."

Genesis & Lady Jaye Breyer P-Orridge - Life As A Cheap Suitcase (Pandrogeny and A Search For A Unified Identity), Summerhall, Edinburgh

www.summerhall.co.uk