Other possible Darth names... going off of the same method from which we get (in)Sidious and (in)Vader
Darth Nuendo- "Is that a lightsaber in your pocket, or are you just happy to see me? I have felt his presence, if ya know what I mean. Who's your father?"
Darth Continent- His bowels always seem to loosen when he calls on the dark side...
Darth Kwell- what could be darker?
Darth Tercourse- You bet he's your father. He's a lot of people's daddies...
Darth Cest- "Luke, I am your father. And your brother. And your cousin. And your uncle. And your grandfather..."