Orla kept scribbling, but knowing that her back was towards him, she reached up with her free left hand and pulled her hair out of it's bun. It fell down over her neck and back, covering up any bits of pale skin that might have still looked tempting. She did so only half-jokingly. One never knew with vampires.
"That's the next experiment, I suppose." She flipped over to a clear side of parchment to continue writing. "Seeing how long it keeps for. In terms of transfusion, it should keep for awhile if I were to set it on ice. For your dietary needs, which again is not what this is necessarily for, I'd think that keeping it on constant simmer for any longer than a week would likely make it taste like bad cheese or something of the like. In other words, you'd probably want it fresh."
She couldn't imagine that to let it congeal and then thaw it time and time again would be any good. And since it was mostly organic, it would begin to go bad and change over.
Orla turned from the book and laid her quill down before walking back over to the cauldron. She took her wand from her robes and began adjusting the temperature of the fire, bringing it up just slightly before she went to add any thinner to it. "You stared at me in school?" she laughed slightly, reaching small vial of clear liquid. "Mightn't of run to girls if I'd known you wouldn't end up looking as squirrelly as an adult as you did back then. Of course, you've traded squirrelly for vampire."