Boy howdy, stop the presses, I just found a secret animation in Coffee With The Crows that only plays if you choose the ace/demi-coded response to the kiss question.

I'm going through my second playthrough, (mostly for fanfic and lore research, who am I kidding, I'm still enjoying the hell out of it) BUT I found that there's this little head-turn and smile that only appears when Rook fumbles and hints to Lucanis that they are also inexperienced in love.

Blink and you'll miss it, but it's such an endearing touch that I'm not sure if others have picked up on yet.