We think it is a fantasy knife and this particular one is known as a Cobra,

Was it my fault that I got out of hand?
--Loki

So you want me to go to a human orgy, where I will not be welcome, and you want us to leave before I get to enjoy myself? ~Eric Northman

A year ago,' I said, 'you wouldn’t have asked this of me.'
'A year ago,' he answered, 'you wouldn’t have hesitated to drink.'
I crossed to the desk and tossed it down.

This letter is written on the skin of one of the water sprites who drowned your parents.'
'Ick!' I cried, and dropped the letter on the kitchen table.

Right and wrong matters little when survival matters most.