He's not expecting it, when it happens. There had been some of this earlier, when he'd been played with, but not to this intensity. It was a compulsion, easily categorized and compartmentalized, before. This, though... this is overwhelming, and he feels himself react in a way he's yet to experience in his few decades of life.

"Uh," he stutters, looking up at her in surprise. He knows what is happening here, but that somehow doesn't make it any easier to resist. He wants to pull away, but... at the same time... wouldn't it be so much easier to just let her do what she wants?

That thought should be enough to make him feel sick. His tail curls around his legs, uncertainly.