Theo had been curious to see what Dominic could do with a dimensional charm, but he understood the reluctance to take on that kind of magic in a relaxed setting; playing with dimensional magic had always given him a headache personally, and while he didn't doubt that his charm-casting prowess wasn't as up to scratch as most people, he couldn't imagine that it was pleasant for anyone else as a rule.
He paid attention when Dominic spoke, in that way of his that unnerved some people, nodding because he too had been guilty of that particular stereotype and feeling worse because of how much he hated the stigma that your Hogwarts House inevitably left.
He was surprised but pleasantly so at Dominic's offer but, to his embarassment, he flinched when the Ravenclaw offered his hand. He'd never really escape that reflexive action, but he suspected that his recent reclusiveness couldn't have helped matters. He tried to act through it, reaching to shake Dominic's hand. "It's Theodore." he offered, sans surname because if anythig made him flinch it was hearing that. "That's very generous of you. I don't tend to get books myself; I was in Slytherin."