Austrian influencer Stefanie Pieper has been found dead at the age of 31. TMZ broke the news that the beauty influencer was found dead in a forest in Slovenia. Her boyfriend, Peter, has allegedly admitted to murdering her. Local outlet Kronen Zeitung reported that Stefanie's body was found after her ex claimed that he strangled her and took the investigators to the location where he'd hidden her. Stefanie Pieper was a makeup artist known for her beauty-related content online. Her ex-boyfriend has since been extradited from Slovenia back to Austria, and investigators have also arrested his brother and stepfather, the outlet has further reported. The details surrounding Stefanie Pieper's disappearance and subsequent death explored: Here's what we know The New York Post has reported that Stefanie Pieper was last heard from on Sunday morning, when she exited a taxi with her friend outside her apartment in Graz. She was scheduled for a photoshoot the following day, though she never made it, local police confirmed. After she went unheard from for days, local authorities issued a missing person report, Kleine Zeitung has reported."We are looking for an adult woman, a missing person report was received on Sunday." Her dog was reportedly found alone in the apartment, and her phone was switched off, Austrian news outlet Kurier has reported. Her ex was arrested at a casino parking lot in Slovenia the following day, shortly after he allegedly burned down his car. TMZ has also reported that data from border crossings indicate that Stefanie Pieper's ex, Peter M., made several trips between Austria and Slovenia in the last few days. He was first investigated for arson, prompting his initial arrest. However, Austria issued a European arrest warrant on Tuesday against him on suspicion of a violent crime. “He was found in the immediate vicinity of the burning vehicle and arrested by the Slovenian police. Extradition to Austria has been requested," a statement read, per The New York Post. Slovenian media have reported that Stefanie Pieper's cell phone has since been located near the border. As of this writing, it is unclear what it was doing there. As for Peter, he appeared at the Maribor district court on Wednesday before his extradition. His reasons for torching his car remain unclear, as do the alleged roles of his brother and stepfather. Details about the case are currently scarce. Stay tuned to SoapCentral for more.