I am a 17-year-old girl. I went to a photo studio and took a very sexy and revealing photo, but what if someone posted it online?

Without your consent, the photo studio posted your photos online without authorization, which violated your portrait rights. You can solve this problem by calling the police, asking the merchants to delete the photos posted on the Internet, apologizing and demanding certain financial compensation. If the other party doesn't want to, it can be solved through court prosecution.