Woody was concentrating very hard to remain his composure as Trisha's hand made circles on his knee. It was hard. Very hard. And Trisha wasn't making the situation any easier. He let go of Katie's hand very suddenly, promptly putting his hand on Trisha's and holding it tight. Just so she would have to stop making the never-ending circles.
He could feel Trisha's eyes baring holes in the side of his head, but he willed himself not to look at her. He mouthed a sorry to Katie, and hoped she would give him the time of day afterwards to explain why he so suddenly had to drop her hand.
"Anyway," Trisha was explaining, "my biology professor is so impressed with my work that he is going to the dean and asking if I can test out of an entire year of this program..." she glanced at Katie, with a flash of her smile to show her pearly white teeth, "and if the dean says yes, it would mean I can graduate at the end of next year, at age 20."
She took her eyes off Katie's and smiled at every one else at the table. She was showing off. Woody knew it. She was trying hard to make him feel like she was superior to Katie. Although he wasn't sure why - they had only used each other for purely sex beforehand.