When Rik Reinking, a German art enthusiast, first set eyes on the bizarre and colourful image, he knew he wanted it in his collection and happily paid €150,000 (£116,000) for it.

He did not care that he would never be able to hang it in a gallery, let alone store it in a vault. This was an example of what some have called “breathing art”: an image tattooed on the back of another person by an artist who was inspired by the author Roald Dahl.

“I’m interested in concepts and ideas,” said Reinking, a collector who likes being at the cutting edge of the art world. “It’s a beauty,” he said of the tattoo by Wim Delvoye, a conceptual artist famous in his native Belgium for breaking social taboos and tattooing live pigs at a so-called “art farm” in China.

For the owner of the back, however, being on the cutting edge was less comfortable. The 30 hours under the needle “was the most awful experience of my life”, said Tim Steiner, a musician from Zurich. “I certainly have suffered for art.”

The story of how Steiner came to be one of the first art-works with an opinion exemplifies the eccentricity of the modern art world and its ceaseless quest for originality. It has also raised ethical and legal questions about “living art”.

Steiner, 30, had to sign a complex legal agreement entitling the 30-year-old Reinking – or his heirs – to reclaim the tattoo from his body when he dies. “I don’t like to think about that just yet,” said Steiner, “but my back will gain a sort of permanence, outliving everyone else. That amuses me.” He has agreed to “exhibit” the work at least three times a year and is about to go on show in a museum in Karlsruhe, Germany.

Steiner, who plays in a band called the Passive Resistance, is beginning to feel responsibility for what is etched on his back but insists his life has continued as normal. “Nothing has changed for me,” he says. “I’m just the frame that gets to carry the picture round.”

For galleries, the arrangement has its advantages. “He’s the only item in my collection that doesn’t require packaging for shows,” said Reinking. “He does need a hotel, though.”

Steiner laughs as he looks back on his beginnings in the art world. A friend who worked in a gallery told him in 2006 that Delvoye was looking for people who might be willing to let parts of their bodies be turned into works of art.

“She told me he was having trouble finding anyone,” Steiner recalled. “I wasn’t surprised. I’d never heard anything quite that outrageous.” Adventurous by nature, Steiner, who was an admirer of Delvoye before meeting him, could not resist the project, which was subsequently bought by Reinking. He has not been disappointed, particularly since being given the opportunity to visit China: he was exhibited recently at an art fair in Shanghai.

“I sit, or stand, facing the wall,” he said. “I am allowed to take 40-minute breaks.”

Delvoye, 43, said that he had been inspired to create art on somebody else’s back by Skin, a Dahl short story about a man who has been tattooed by a famous artist. A heavily varnished version goes on sale in Buenos Aires and it is implied that the man has been murdered by art dealers.

The main difference between working on pigs and people was that “the pigs never had an opinion”, said Delvoye. What is more, the tattooing of a human has not provoked animal rights activists who have protested about some of his exhibitions in Belgium. In fact, he says, the pigs are treated humanely at his Art Farm in China. They are given sedatives before being tattooed. Collectors can buy them live or purchase their tattooed skins when they die of old age.

With plenty of food, he claims, the pigs enjoy better living conditions than millions of poor Chinese. Reinking, however, believes that the “religious motif with different figures, including koi carp” on Steiner’s back is Delvoye’s best work. “I’m not interested in pigs,” he said.

Another of Reinking’s favourite artists has made a name for himself by selling his own history. “You can buy 10 minutes of his life for €150,” he said. “I have an agreement with him, buying two photographs of him a day. We’ve been doing it for 13 years so there are thousands of photographs in the collection.” The British art critic Ben Lewis, who sports a Delvoye on his shoulder – a tattoo of Mickey Mouse on a crucifix with Minnie weeping at the base – tried to have it valued at Sotheby’s but was turned away. The auction house said it would be worth more on a pig because it might decay on him.

As for Steiner, he is getting used to life as an objet d’art. “We’re starting to grow together,” he said of his tattoo.

He hopes, though, to avoid the fate of the man in Dahl’s story.

Additional reporting: Sara Hashash

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