Kyle gets a text form Mr. Knuckles:
'Tell me the best way to kill a domovoi.'
((I'll let Elf answer that one))
"T-T-Thank you f-for helping..."
He nods.
"My job is to protect the principal."
Killing one? Possible- long as you can kill it's damn hard to kill physical body, it's dead. Incinerate it first. And then split the ashes apart. Permanently? Well, nobody's ever killed a domovoi permanently. Ever. They've chased them off, forced them to never return, or killed their family before they can reform, but never actually killed one that stayed permanently dead yet.
So, really, focusing a domovoi is a really stupid idea. Kill their family instead. Most aren't inclined to avenge their family and move on.
((Been hunting on the Internet for actual ways to kill one- there isn't. They can be chased off from their principal's house or banished.
Also because this fits into some lore on Cheru I'm going to reveal at some point and to a certain extent Carrick.))