Ignore it and cum.

I quickly realize they are walking towards us. I'm not sure if it was the excellent job from my step-sis or the excitement of getting caught but I was at the point of no return.

I was cumming and cumming hard. The first shot she caught in her mouth with a moan. Then she kept stroking my throbbing cock with her tits but not sucking the tip, the next shot of cum over her gorgeous tits and neck. I tried to look in the reflection of her sunglasses but when her head came up as I came it disappeared into a blue sky.

Shit I could feel whoever it was approaching behind me. I couldn't see them but I could feel it. I sat up and leaned slightly forward, my cock still between her tits, and still cumming. I saw the shadow to my side as they got closer. I looked down and saw my sis staring up as me, the tip of my cock just barely peeking up between her tits as another shot of cum spurted up onto her tits.

I see the shadow stop, I'm still cumming when I hear "Hey Amber? Can you help wi, Oh! I didn't realize you had company."

I turn and look back.