I really hope the lead ring generated by the binding contract supress the typical lead trouble: Plumbosis
Yeeeeeeaaahhh that's something we failed to touch on, that's on me! The idea we had is that the lead ring only looks and feels like lead, in truth it's made of some magical material unique to the realm. So no worries, the MC won't get lead poisoning.
...We should probably fix this in the story though, h-haha.