Situational sexual behavior means that different people feel comfortable doing different things when it comes to sex in different situations. For example, someone might feel comfortable having sex with a long-term partner in a bedroom, but not with someone they just met in a public place. Another person might feel comfortable doing more adventurous sexual activities with someone they trust, but not with a stranger.
It's important to understand that everyone is different and your feelings about sex may change depending on who you're with and where you are. It's also important to respect other people's boundaries and understand that just because someone feels comfortable doing something in one situation doesn't mean they'll feel comfortable with the same thing in another situation. Communication and consent are key!