Finger your prostate

As Sumi is jerking me off with her left hand, I can feel her right hand go for my ass, which she promptly grab and caress. It's kind of a weird feeling, as I'm not used to having someone play with my ass.

"Just thrust mommy." She says, as I can feel that her finger is now gently caressing my asshole. I clench my cheeks as a reaction, but between Sumi's touch and soothing voice, I stop struggling and let her do as she pleases.

I feel confused by her caressing my asshole. It's a whole new different feeling, but I don't necessarily hate it. Hearing me moan, Sumi takes that as an invitation to slide a finger inside my ass.

I gasp at the sudden intrusion. The feeling of pressure and fullness in my ass is something I've never felt before, but as I'm thinking of stopping her, I can feel her finger hit what must be my prostate, making me squirm in pleasure.

Still on her knees, Sumi keeps teasing my ass, sliding her finger in and out expertly poking my prostate. It doesn't long for me to feel what is most probably the best orgasm of my life yet, and blow my load which, unfortunately, barely hits Sumi.

I tried to sneakily shift my hips so that my cock would shoot towards her, but past the first stream that hit her apron, Sumi shifted my cock away, making me cum all over the floor.