"Tithe your blood to me, and in exchange I'll ensure you spend the rest of your days in comfort."
Poor Santiago is unfortunately one of many hit by the latest wave of tech industry redundancies, and without a decent job offer he's willing to take, he's desperate for a stream of income; it's too bad that the blood plasma donation center near his apartment is indefinitely closed for renovations. Just before all hope is lost though, a stranger passing by offers him some company for the evening, and much, much more not too long after...
But... there's always a catch to these things, isn't there?