Feeling up Millie's big tits

I kneel down next to Millie's sun lounger, and put my hands back on her tits and start caressing them, then I lean in and start kissing them, slowly kissing my way towards her nipples.

Millie has her hand in my hair, holding my head in place against her tits, and her breathing is intensifying.

I feel nervous that soon she will tell me that we have done enough of this, but so far she seems very content with allowing me to enjoy her big tits to the fullest.

My dick is straining against my shorts, and it is so hard that it almost hurts. I don't want to use one hand to jerk myself of, but then I feel Millie's arm that is on the side of the sun lounger where I am kneeling slowly moving, and then her fingers are tugging at my shorts, trying to pull me closer. I shift my body forward a bit so I am within reach, and I feel Millie's hand stroking my dick through my shorts.

We stay like this for a while, I am sucking on Millie's nipples, and she is touching my cock through my shorts. Then Millie moves her hand and pulls my shorts down, then her hand grabs my dick and she starts jerking it slowly. This feels so amazingly good.

I slowly stand up, Millie's hand stays on my cock still jerking it, I move one leg over to the other side of the sun lounger, then move my body down so I am straddling Millie, but not sitting on her, I balance most of my weight on my feet.

My cock is now inches from Millie's big tits, and she is jerking it slowly, while I am massaging her big tits. Very slowly I move my body up so my cock gets closer to Millie's breasts, and then finally, the head of my cock makes contact with Millie's right breast. I keep moving forward, my cock sliding along the bottom of Millie's right breast, then the right breast ends, so my cock no longer touches it, but as I am moving forwards, my cock soon bounces into Millie's left breast, then moves forward along it down the increasingly narrow valley between her big tits.

Then, my cock is so far in between her big tits that it now has contact with both her breasts at the same time. I have gotten my cock between my step-mom's big tits!

Millie is still slowly stroking the part of my shaft that is not between her tits, but then she lets go of it, and I fear she is about to open her eyes and tell me that we have gone too far, but instead her hands move to the side of her tits, pushing them together around my cock, and without opening her eyes she whispers:

"Go ahead."

I know exactly what she means, so I slowly start sliding my cock back and forth between her big tits, struggling to believe that I am tit-fucking my step-mom Millie!