Ah, but there's the rub. Penumbra aren't your traditional vampyre. There is occasion they partake of sanguinism, be it ceremonial or life-threatening situation. They are cursed, but blood lust is not part of it. Blood is sweet to them, in particularly those of relatives and companions and they've somewhat a sixth sense of such. It's more common they have their blood partaken as it grants vitality or classical vampirism in others, which is what Umbra are. I've not fully decided on what a Penumbra desiring blood would entail.

As for Rochel, she's the baby and often spoiled and will pout, so she does get her way when she wants it.