I'm so sorry about resurrecting a three year old thread but to be fair, when Marisa meets her in EoSD, Remi describes herself as a "light eater" who "always leaves some" so there's a fine precedent for her being bad at drinking blood neatly.
More importantly this was adorable ;u; and as much as I savor the melancholy of mortal Sakuya, I also love the idea of her stepping into the same tempo as Remi by volunteering to be turned.