The only way you could get pregnant that way would be for semen to leak from your anus to your vagina, which is highly unlikely. But that doesn't mean anal sex is completely safe—so don't let a guy try to convince you that it is. See, unlike the vagina, the anus doesn't have much lubrication, so its tissues are prone to tearing, making it easier for STDs (including HIV) to enter your body. So using condoms is a must. And even if the guy is wearing a condom, no one should have vaginal sex after anal sex unless the guy washes his penis with soap and water first and then puts on a new condom. The anus is filled with bacteria that can cause serious infections if they get into the vagina.

Generally speaking, sex is any intimacy that gives you physical pleasure—which can include touching, kissing, oral sex, rubbing, whatever. Besides doing these things, some lesbians do use sex toys to penetrate the vagina. But just because they don't have penises doesn't mean they don't have sex in other ways.

Yes, it can happen, but it's not very common. Sperm can live outside the body for up to 48 hours, so if a guy has some on his hands and then puts his fingers inside your vagina, there is a risk of pregnancy.