By Amanda Pearson   Barbie’s Underwear The sexual exploits of a girl in second grade always revolve around her Barbies. My sister’s friend Anna, who lived next to us in our old neighborhood, was two years older, and she told me she knew what she was talking about. “You have to be naked,” she said as we sat on her bed. The air was dusty in the dark light that streaked through the blinds. She had Ken and I had the bleached-blonde Barbie. After we got the clothes off, Anna grabbed Barbie and started smacking the two tanned dolls together. Barbie was never actually naked, which Anna wasn’t happy about, but the painted-on swim suit was something we couldn’t remove. She showed me that…