Bob nodded.

When Susan removed her hand, Bob kept rubbing his palm up and down his mother's crotch. Susan cupped his cock and balls, feeling them through his trunks. She gurgled as his cock started to swell again.

"That's enough," she whispered, petting his cock and balls, then removing his hand from between her creamy thighs.

Pamie and Billy were coming toward the hot tub. Susan's eyes raked across the front of Billy's trunks, searching for signs of his cock. She could see the puffy pouch of Pamie's cunt, and she began to dream up images of them naked, all of them, outside on the patio, using the hot tub, seeing each other and feeling and… fucking?

Susan was shook by the thought.

Fucking? With her sons and daughter? Taking her son's cock into her cunt, fucking him frantically, watching Pamie fuck her brothers? The image was so strong, Susan came again, stronger than before, a shuddering orgasm that almost frightened her. She didn't know enough about her children. Maybe they weren't as interested in sex as she was. Maybe they didn't care about such things. Maybe they wouldn't have anything to do with their mother that way, or with each other.

She watched Pamie and Billy slip into the hot tub. With all four in it, there wasn't much room. Maybe two more people could get in, but Susan had no intentions of using the tub for six people.

She felt her daughter's thigh brush hers as Pamie settled down, Billy on the other side. Almost immediately, she felt the movements under the water. She looked at her daughter and Billy. They looked so innocent, so sweet, yet Susan knew things were going on under the water. Pamie had rested her head on the deck, her honey blonde hair framing such a sweet, innocent face. Pamie turned her head toward her mother, smiling. Her sky-blue eyes looked different to Susan, and then she understood. Those young eyes appeared hot, almost glazed. Then she was sure of what was happening beneath the water. Billy was sighing happily, his eyes closed.