Really!?

[She never knew demons came from vampire since in her world demons are created from the negative aspects from a group of individuals. Sometimes, even a living person can feel like one by their demeanor.]

Then under no circumstances are you allowed to starve, Yuu!

[All said rather loudly as she doesn't want him to turn into one or else she'll have to fight against him.]

Is there a food source vampires have other than blood? Or is it just blood as their diet?