Tuberculosis preventive treatment (TPT) is increasingly provided to adolescents and young people living with HIV (AYPLHIV) in high-burden areas. Research indicates that tailored support enhances AYPLHIV’s engagement with HIV treatment. A study conducted in Harare involved focus groups and interviews with peer counselors aged 18-24 who had been offered TPT. Findings revealed a disconnect between healthcare workers’ presentation of TPT as routine and the participants’ challenging experiences with it. Many discontinued TPT due to a lack of support, despite some being motivated by personal circumstances, such as witnessing severe TB illness or pregnancy. Side effects and stigma associated with TPT contributed to treatment discontinuation, impacting adherence to antiretroviral therapy (ART) and overall mental health. The study proposes five guiding principles for supporting AYPLHIV in multimorbidity care: fostering supportive relationships, delivering tailored messaging, providing adaptable support, respecting autonomy, and timing interventions effectively. These principles emphasize the importance of consistent peer support and the need to prioritize AYPLHIVs’ agency and well-being in health decision-making, aiming to improve treatment outcomes and address the biosocial complexities of their care.