My sister, who goes to a slutty girls' school, has a weak personality, so she can't refuse when she's asked out, and it seems she's been getting fucked by various men! So I, a virgin, strongly asked her if I could practice sex with her, and she said, "It's okay if I just touch your pussy..." and it turned out to be a godly development! When I spread, pulled, and rubbed her pussy for the first time, her love juices started dripping and she was completely wet! My slutty sister was in heat, and even though I knew it was wrong, I couldn't resist and ended up fucking her!