Learning to say no is great, respecting yourself and your body is awesome! But sex exists within limits and taboos. Also, you'll notice she suggested using an inside condom for anal sex, but that's not FDA approved (ie, it might not protect at all. Even using a condom in the way they were designed to be used, you're still taking a risk of getting an STD or a surprise pregnancy. Or in a monogamous relationship, infections that aren't STDs like yeast infections can be passed back and forth.