Context: In Amsterdam, American backpackers Paxton (Jay Hernandez) and Josh (Derek Richardson) and Icelander Oli (Eyor Gujonsson) meet Alexei (Lubomir Bukovy), a Russian man who tells them about a Slovak hostel filled with American-loving local women. The backpackers board a train to Slovakia, where they meet a Dutch businessman (Jan Vlasak) long enough to be unnerved by his bizarre behavior. Upon arriving in the small village, the backpackers check into the local hostel and find themselves sharing a room with Natalya (Barbara Nedeljakova) and Svetlana (Jana Kadeabkova), two attractive, single women who entice the backpackers to a spa and a disco before sleeping with them.Tthe next morning, Oli is missing. A young Japanese backpacker named Kana (Jennifer Lim) also reports that her friend Yuki (Keiko Seiko) has disappeared. An MMS photo sent from Yuki's phone shows Yuki and Oli beneath a smokestack of an abandoned factory, with the word Sayonara written beneath it. Unbeknownst to Josh and Paxton, Oli has been decapitated and Yuki tortured, and (presumably) killed. Paxton and Josh decide to leave Bratislava with Kana the following day. They spot a man wearing Oli's jacket at a museum of medieval torture relics. Paxton later notices that in the MMS photo of Oli, Yuki and the smokestack is faked. Later that night, while partying with Natalya and Svetlana, Paxton and Josh succumb to the effects of alcohol. Josh stumbles back to the hostel while Paxton passes out in the disco's storage room.Hours later, Josh wakes up handcuffed to a chair in a dungeon-like room surrounded by power tools and weapons. The Dutch businessman enters in a leather apron and gloves and begins torturing Josh, drilling him in his pecs just above his nipples. After he is done, the Dutch Business man sits down and talks to Josh, explaining his unfulfilled dreams of being a surgeon. Josh begs to be released, the businessman then cuts Josh's Achilles' tendon and lets him crawl towards the door before finally murdering him.Across town, Paxton awakens and returns to the hostel to find both Josh and Kana missing. In his room are a different pair of beautiful women inviting him to a spa, eerily similar to Natalya's and Svetlana's offer from before. When the local police chief (Miroslav Taborsky) proves unhelpful, Paxton locates Natalya and Svetlana and demands to be taken to an "art show" where he thinks his friends are. They drive to a factory on the outskirts of the town where inside, Paxton sees the Dutch businessman cutting up Josh's dead body. He screams at Natalya, who laughs at him, and he is then ambushed by thugs who drag him past cells filled with other backpackers being tortured by various clients.Paxton is taken to his own cell and restrained to a chair, joined minutes later by a German client (Petr Jani) who tortures him. Distracted by Paxton's ability to plead for his life in German, the client puts a ball-gag in his mouth and tries to kill him with a chainsaw, but before he can begin Paxton starts throwing up, either out of fear or because the gag was choking him. Due to his ball-gag, he starts to choke on his own vomit, and the client quickly removes the ball-gag, probably to stop Paxton dying before he could kill him. He then continues his torture with the chainsaw, but inadvertently saws off Paxton's handcuffs along with his ring and pinky finger before slipping on the ball-gag which he just threw on the floor. The client drops the chainsaw on his own leg and severs it.Paxton breaks free and shoots the client in the head with a gun on the weapon counter. When the guard comes to check on the situation, Paxton shoots and kills him before escaping dressed in torture gear. He hides in a nearby room to avoid capture from other guards, where he finds a collection of victims. He hides under a pile of body parts before being taken to a room where he sees dead bodies being chopped up by a butcher for cremation. Paxton kills the butcher with a hammer, 
 Question: Who kills Natalya, Svetlana, and Alexei?
Output: the client drops the chainsaw on his own leg and severs it