"I simply meant that if we find ourselves in the presence of mistletoe again I will know how to react appropriately."

Yeaaah, definitely thoroughly flustered now. And perhaps a little confused.

"I, ah. I would assume that it would be presumptuous and inappropriate of me to press for more."

He's trying not to focus on how nice it felt, or how smooth her lips had been against his, how warm they were, how--no, no. Think about something else.