There is one way I can think of it, though it still doesn't sound quite right--

In my world, there is a concept of Equivalent Exchange. In alchemic terms, it means you can only create something out of an equal amount of something else. You can only make a teacup if you have the exact amount of carbon, nitrates, and other materials needed in raw form.

A life is different from an object, but a savvy enough alchemist might find risking their own life and limbs-- literally, for the power to attach a soul worth the danger.

[tl;dr someone probably got his arm ripped off]