Nice entries here, but I think it's a tossup between Amai Liu (aka Tiny Tabby) who stands 5'1" and weighs 74 pounds, and Zuleidy (aka Little Lupe') who's 4'11" and weighs 85 pounds. They have among the smallest asses in porn. If I had to choose one, I'd go Zuleidy since she does anal. I'd skip vomit breath Amai Liu since at 74 pounds she'd probably spit out miscarriages like pez.