He's trying to think of a way to reassure her that it's okay that she isn't a dancer, but Angeal then noticed the squeeze which actually helped him. "Then that will make two of us." Which was better because the last time he danced was..some holiday ShinRa party or other a long time ago, a lifetime ago basically.

But the First Class blinked at hearing what she said.

Wait, what?

Angeal clears his throat and works on shaking the compliment off because Aerith's next words really got to him more than she could know, considering what he put Zack through and here she was being kindness itself.

"Thank you" He hesitated a moment as he attempted to digest her words and then nodded. "Let's get on the dance floor then."