@HoodedClaw
What sort of ring is it? If it's the silver titanium one then irritation would be rare as titanium is supposed to by hypoallergenic. Or is it the stealth bomber with the coating that may be causing irritation?
I suspect it's more that the skin underneath is damp for too long, for whatever reason. So less a reaction to the ring and more a reaction to skin being covered by the ring in a way different than paulguy is used to not having worn one before.