Thanks for the advice, but not only had I lived that very same dilemma before and wish to avoid burrows outside of real emergencies... the gold demon, after slapping on her pursuers' noses with her human bone crown, humain nail amulet and other girly accessories, disappeared from the map along with half the siege after the first half broke all their bones falling from the Dodge-ThisŪ. No trace left from her. Nobody landed a hit on her, so no drawn blood. She also disappeared from the civilization list. Must check where she ran away to in Legends later.
Have no fear, however! The first unwanted visitor from the deep also has deadly blood. EDIT: and the second one, too.
On another note... I forgot to mention it, but once again, the siege coincided perfectly with the visit from my elven neighbours.
They all survived; their llamas didn't. They stayed a bit at the depot afterwards, probably looking pissed, as even if I wanted to buy all the stuff they brought, they had nothing but their delicate hands to carry my tons of rock crafts.
I really, really like that running joke, and congratulate myself vigorously for building that trade depot outside the fort.
Last thing: stop making so goddamn many artifact jewelery. We have more bracelets than I have arms. Most reference each others. Screw you, guys.