Individual differences are unique characteristics that develop over the life of the individual, and are formed based on genetic predisposition and lived experiences. These individual differences can modulate (inhibit, favor or amplify) the expression of behaviors, including risky sexual behaviors. Sexual risk behaviors are those that expose the individual to physical risk, such as being affected by sexually transmitted infections (STIs), and to social risk and vulnerability, such as early pregnancy. The objective of this work is to investigate the individual differences that are related to the propensity for risky sexual behaviors, as well as variables related to the individual's characteristics, such as the use of HIV pre-exposure prophylaxis (PrEP) and non-monogamous tendency. Data collection will be done online and participants must respond to personality measurement instruments, impulsiveness in decision making, search for sexual sensations, life history strategy and socio-sexual orientation, in addition to a sociodemographic questionnaire with information on sexual behaviors of risk. In recent years, there has been a huge increase in the number of people who have contracted sexually transmitted infections here in Brazil. The human immunodeficiency virus (HIV) has no cure, while other STIs, such as syphilis and gonorrhea, are curable, but are beginning to develop resistance to antibiotics. Therefore, prophylaxis is the most efficient means of combating the spread of STIs. Based on this, this work will contribute with information related to this public health problem, providing a greater understanding of which individual characteristics are related to risky sexual behavior, and thus, collaborate so that intervention means are more effective, preventing more people expose themselves to risky sexual behavior.