He grins again, thoroughly enjoying the idea of watching Ianto check out the stock and seeing what grabs his attention. They've already visited the shop together in the past, of course, but it's changing quite a bit under his ownership and also this is a bit different, a bit more specific, now that Ianto's expressing such a strong interest in kink.
He very much enjoyed Ianto surprising him by requesting a spanking, back in the library, and he's looking forward to seeing where else this leads them.
He chuckles at the news that apparently Spike expresses exactly the same opinion about his tastes to Ianto as he does to him. "Well, I've already established he's into pain at least a little, so I'm thinking nipple clamps might be a thing to try. But probably more vibratory things. He's still so new both to anal and to anything kinky, I'm wary of going too far and spoiling it all for him!"