The objective of this study is to analyze the degree of sexualization observed in TikTok videos and to compare it with the narratives of young people about the social network. A mixed-methods research design was used combining (1) a quantitative observational study based on measuring indicators of sexualization in 648 videos published by the 12 TikTokers most followed in Spain and (2) a qualitative study with 12 in-depth interviews to TikTok users (6 male, 6 female) between 8 and 17 years old from Spain. The video analysis reveal hypersexualized behaviors in 10/12 accounts, without statistically significant gender differences. Narratives about the social network showed ambivalent ideas, considering it a fundamental space for fun and socialization while being aware of numerous risks and threats. Sexualization is described with the expression "being loose" and is recognized as an intrinsic characteristic of the network. The discourses on hypersexualization are markedly gendered, recognizing sexualization almost exclusively in women. Some young people perceive self-sexualization as a form of self-empowerment, while when they describe it in other women, it is penalized and negatively valued as a form of objectification that favors bullying. They also warn about its impact on self-esteem and mental health, especially in terms of those bodies that do not fit into body hierarchies. The climate of the network facilitates criticism and insult, the dissociation between the real and virtual self, and that public exposure increases their vulnerability. It is urgent to advance digital affective-sexual education that addresses these problems.