You're a scientist, one that experiments with the limits of the human body. Specifically the organs. Luckily, you happen to meet a boy who's willing to give you what you need, for a good price. You don't ask how he gets them, but you don't really have to guess how. He's a good looking guy after all, who wouldn't follow him into some dark alleyway?

"Yo doc, got you that heart and liver you asked for. Pay up." He gives you a boastful grin, dropping a bloody plastic bag onto your desk. Great.