It took Dean a few seconds to parse exactly what Dennis was saying to start with and then he sighed, setting down the chip he'd just picked up. He looked at Dennis and took a couple of seconds to work out what to say. Thankfully he wasn't being shouted at, as that would have managed to really piss him off.
He decided to skip over Susan's involvement, frankly that was too long a story to share with a nosy berk like Dennis. "I'm kind of fed up of having this conversation with one friend or another," he said. He held up fingers as he counted off his points. "I do not have feelings for him, he does not have feelings for me, and we do not flirt. We're friends, we're close. We hug sometimes, big whoop." His words were dry and pointed, fed up of the general theme.