Yeah, they're demons for jewellery, even necklaces. I stopped wearing those when my favourite pendant was irreparably gouged by little teeth. They'll also remove bandaids, trim your fingernails and hangnails, inspect your ear canals, eat your watch band and try very hard to crawl into your mouth so that they can clean that too. Honestly, even just wearing little studs in your ear lobes is begging for bloodshed. The more an object smells like their favourite person, the more domestic rats will want to play with it... and play means "destroy". A piercing is a double jackpot for a rat. It counts as both grooming and a play object.