My friend Kelly told me about a boyfriend she had some years ago who gave her some great foot massages. He would take one of her socks off and start with her ankle. He'd gently rub all around that before moving down to her heel. He'd work his way up from there, pressing his thumbs into her arches and under the ball of her foot, until she seemed thoroughly relaxed. Then he'd move up a little more and rub her just under her toes.
Toward the end, he would take each one of her toes and pull it gently from the foot toward its tip. He'd put a finger between each pair of toes, and gently squeeze as he moved his finger back and forth between them. Last, her big toe would get lots of attention. When he was finished with each foot, he would lift it and give it a little kiss, and then put it back in its sock.
Kelly found that these massages relieved a great deal of tension, and was happy to receive them. But one day she noticed when he was finished with one foot, he would always set it down right in his lap. She wondered if it was pressing on his dick while he was massaging the second foot. Of course, since he'd be moving a little as he did the second foot, the first one in his lap must surely cause a little rubbing of his penis, and she wondered if he was secretly enjoying himself from that stimulation.
She thought she might find out if she moved her foot a little more than it would move just from her boyfriend's massaging. She didn't want him to know she was trying to get him hard, so she would stretch, or cough, or pretend to get more comfortable by shifting her position. But with each twitch of her restlessness, she would make sure that her heel would give him a little back and forth stroking.