Austrian Influencer Stefanie Pieper Disappears After Christmas Party; Ex-Boyfriend and Relatives Arrested in Expanding Investigation

28 November 2025

Beauty influencer and makeup artist Stefanie Pieper, 31, vanished under mysterious circumstances after attending a Christmas party in Graz, Austria, a disappearance that has triggered a cross-border criminal investigation and the arrest of her former boyfriend and two of his relatives.

Pieper was last seen at dawn on Sunday, November 23. According to police, she arrived home by taxi with a friend and was dropped off near her apartment building. She was expected Monday morning for a scheduled photoshoot, an appointment she failed to attend. Concerned, the photographer visited her residence and was met not by Pieper, but by her 31-year-old ex-boyfriend, identified only as Peter M.

Inside the apartment, authorities discovered unsettling signs: Pieper’s dog was alone, a phone belonging to the influencer was recovered discarded in a nearby bush, and local media reported that neighbors had heard loud noises around the time she returned home. One of her final messages to a friend reportedly warned of a “creep” lurking in the stairwell, describing a “dark figure” a chilling last communication.

The situation escalated rapidly. On Monday evening, police in Slovenia arrested Peter M. after a red Volkswagen Golf found parked in a casino lot in Šentilj was discovered ablaze. He was reportedly found in close proximity to the burnt vehicle. Austrian authorities immediately requested his extradition.

In addition to Peter, two of his relatives believed to be his brother and stepbrother have been detained in Austria as part of the ongoing investigation. Police are conducting extensive searches: sniffer dogs have been deployed to sweep possible locations linked to the suspects. So far, no trace of Pieper has been found, and authorities stress that rumors claiming she has been located are unfounded.

The disappearance has drawn widespread attention, not only because Pieper has a substantial social-media following but also due to the disturbing contradictions in the timeline and evidence. The contrast between her final messages asserting she’d returned home safely and the police findings has deepened concerns that foul play may be involved.

Pieper’s mother has made a public appeal for help, offering a financial reward for any information that could lead to her daughter. The community of Graz and social-media followers internationally have responded with messages of concern, solidarity, and calls for justice.

As investigators comb through evidence and cross-border leads continue, the spotlight remains on unanswered questions: Who was the “dark figure” Pieper feared? What happened between the taxi drop-off and the alarming sounds neighbors heard? And most critically: where is Stefanie Pieper now?