On the rooftop of an empty building in Zagreb, Dino Helvida carefully pierces his client Kaitlin's torso, legs and face before putting hooks through her skin.
Shortly after, he suspends her from a metallic frame, her heavily tattooed body dangling horizontally in the air.
Helvida, 27, is a professional piercer and body suspension expert from Bosnia Herzegovina, who for the last six years has been hanging up the bodies of those brave enough to partake in what is an extreme form of body piercing, sometimes for hours.
"You can do one hook or you can do 100. You have different hooks for different positions and different hooks for different body parts," said Helvida.
"So everything is really calculated and it's safe."