The first case involving repetitive sexual abuse linked to the use of buprenorphine is reported. Under the tradename Subutex, buprenorphine is largely used for the substitution management of opiate-dependent individuals, but it can also be easily found on the black market. A 14-year-old boy was found dead at the home of a well-known sex offender of minors. At the autopsy, no particular morphological changes were noted, except for pulmonary and visceral congestion. There was no evidence of violence, and no needle marks were found by the pathologist. Toxicological analyses, as achieved by liquid chromatography-mass spectrometry, demonstrated both recent and repetitive buprenorphine exposure in combination with nordiazepam. Buprenorphine concentrations were 1.1 ng/mL and 23 pg/mg in blood and hair, respectively. The boy's death was attributed to accidental asphyxia in a facilitated repetitive sexual abuse situation due to the combination of buprenorphine and benzodiazepines, even at therapeutic concentrations. The use of buprenorphine as a sedative drug was not challenged by the perpetrator.