Sexual interest in minors (i.e., pedophilia and hebephilia) is considered a risk factor for Child Sexual Abuse (CSA) and the use of Child Sexual Abuse Material (CSAM). This study examined the long-term development of CSA, CSAM use, associated cognitions, and quality of life among self-referred, help-seeking individuals diagnosed with pedophilic or hebephilic disorder (PHD) outside the judicial system. Of the 110 eligible men who had undergone therapy for PHD due to psychological distress or risk of offending, 56 were available for follow-up assessment 1–11 years after treatment. Behavioral manifestations, offense-supportive cognitions, and quality of life were evaluated using interviews and psychometric measures. At follow-up, 7.7% of participants with a history of CSA had re-offended, whereas 89.1% of previous CSAM users reported recidivism, although with less severe material. No new CSA offenses occurred among those without prior CSA. Treatment led to increased cognitive victim empathy and reductions in CSA-supportive and CSAM-supportive attitudes, but only the latter improvement persisted through follow-up. Participants exhibited elevated CSA-supportive attitudes relative to community norms at all time points and diminished quality of life at follow-up. Pedophilic and hebephilic disorder carry a persistent risk of sexual offending, particularly regarding CSAM use. Therapeutic gains in offense-supportive cognitions may erode over time without ongoing care. A comprehensive public health approach encompassing early detection, prevention, and expanded treatment access that addresses both the risk of reoffending and overall well-being is crucial for reducing sexual victimization and improving mental health outcomes for individuals from this target group.