AQN said you'll turn into a ghoul-like thing and the sun will evaporate you.
But this would happen only if she drank all your blood, and as she is a light eater you'll be safe.
If no blood is drawn then you aren't submitting properly to Remilia Ojou-sama.
That incommensurable anguish when no qt vampire loli ojou-sama to force you to give her horsie and crawl on all fours over broken glasses, nor to whip you back and lick the bleeding wounds, nor will she grab your balls with her cold bare loli hands and slap your painfully erect cock.
Why even exist.