Mark woke up early the next morning surprisingly feeling no ill effects from all the drinking at the Christmas Party the night before. He did drink quite a bit, but also ate a full meal and did quit drinking about an hour before leaving the party, so he had sobered up some before driving home. Wandering up to the front of the house he noticed his dad passed out on the couch. Looking out the front window, he saw his parent's car wasn't there so he guessed they took a cab home.
He walked into the kitchen and grabbed a quick drink of water before heading back toward his bedroom to get dressed. Passing his parents room on the way, he noticed their bedroom door open, but when he peeked in, he didn't see his mother in bed. Wondering where she might be, he stepped into their room and only then did he hear the shower running. The bathroom door was open so he walked over to it and peeked his head inside, noticing his mother in the shower.
Remembering what she told him the night before about having time to do more, he slipped into the bathroom and quietly closed and locked the door. Watching his mother behind the obscured glass on the shower, he quickly pulled off his tee shirt and jockey shorts. His cock was already hard as he moved over to the shower and opened the door.
As he stepped into the shower with his mother she said, "Oh Henry, are you sure you're up..." she paused, after wiping the soap out of her eyes and said, "Mark?"
"You said we could do more when we had more time," Mark said.
"But your father..."
"He's passed out on the couch, besides, I locked the door," he said, soaping up his hands and reaching out to her. Her back was to him so he reached around her from behind and cupped both her breasts in his soap hands. Squeezing up behind her, he slid his erection against her ass, moving it up and down her soft skin.
She turned to him then and he let the water rinse off his hands and her breasts. Mark then leaned forward moving his mouth to her left breast as his hands dropped down to her ass. He kneaded her ass as he sucked on her nipples, first the left one, and then the right. Arching her back, she pushed her breasts out to him as she reached her hand to his head. He felt her push his head downward, so he kissed and licked her wet skin down her breasts, over her stomach, through the dense patch of pubic hair and onto her pussy lips.