[This time, the way Ren's smile tweaks is into something more playful and amused. He could certainly think of a few reasons someone close to him might get him a tag for his collar, and he's not letting Chuuya get away with a subject change quite that easily.

Of course, he's not about to ignore the compliment, either, but he does bypass it for a moment to curl his fingers against his lower lip as if in thought.]

Oh, so it's like that, is it? Don't worry, I won't tell, since you made that cute a look. [And then he winks, as if it wasn't obvious enough what he was getting at.] It seems like you have pretty good taste, though. I appreciate it~

[It's hard to tell whether that should be taken as a return compliment, accepting the compliment, or both.]