Her bum

When Erin slips, she finds herself on her bum and her skirt open, causing her dark green short skirt to slide up to her hips, exposing her bald pussy. The fall also made her giant breasts pop out the bottom of her light turtle neck shirt, exposing her long nipples. For all pretense, Erin was effectively naked.

Feeling the cool breeze on the muggy day against her pussy and across her titties was a welcome sensation. However, her slip was in the public eye of bystanders and passerby-er's.

With her knees bent and legs spread and her arms behind her, propping her up she and her pixie cut hair covering one of her eyes, she stared as several of the men grew erections that popped up out of the waistband of their shorts.

Feeling a bit silly, she started to stand up to bring a bit more modesty to her appearance and tuck her boobs back up under her turtleneck shirt, but she was surprised when a hand reached under her arms and began groping one of her exposed tits. This caused her to freeze and look around for the owner of the hand. When she looked to her left she saw a man whose arm was extended almost 2x as long as normal and whose penis was standing so erect, it was poking him under his chin. She was about to say something when another hand began fondling her other tit and nipple. Now looking to the right she saw a similar sight.

Ogling in jealousy the mens over-stretched penis' she immediately became very, very horny. She wanted those cocks, but more than that she wanted her own holes stretched.