Background: High-risk sexual behavior, including unprotected sex, is highly prevalent in adolescents (13-17 years old) and exposes them to unintended pregnancy, HIV, and other sexually transmitted infections (STIs). Two explanations for why young people are more likely to engage in high-risk sexual behavior are that individuals do not perceive themselves to be at risk, and individuals do not feel they have the autonomy and agency to affect control over their reproductive health. Reaching adolescents who do not think they are at risk for unintended pregnancy or HIV/STIs and/or do not believe they have the agency to reduce these risks will take novel approaches. “Serious games,” defined as videogames for purposes other than just entertainment, can be developed into interventions for improving health behaviors and are a recent innovative and effective way to reach at-risk populations, including adolescents. We hypothesize that by employing videogame technology we can develop an interactive mobile game application (“app”) for smartphones that can be played by individuals in their social networks and teaches and models the consequences of high-risk sexual behavior and lack of personal agency, including unintended pregnancy, and HIV/STI acquisition. Games that model risk assessment and risk management may decrease high-risk sexual behavior among adolescents, which could have far-reaching implications for public health, and a practical and positive domino effect for communities.