"Why should I?"

She shrugs. "Why not? It's not like I'm going to be a threat, I don't particularly care about Sith politics and you seem at least less petty than the current Lord you want to kill."

"Coddled little Jedi. Everyone is a threat."

"And yet, someone taught you."

"Didn't exactly work out well for her. I killed her."

"Why?"

"Does it matter?"

"Yeah, actually."

Occlus snorts.

"She was trying to kill me. Though I would have done it unprompted not much longer after it ended up happening."

"Would you? Why?"

"Because she would have had little left to teach me, and I would have been in a position to do so securely."

"...that sounds like a terrible reason, why do Sith teach each other anything around if they just want to kill their teachers for no good reason?"

"Because occasionally the short-term benefit of having a helper outweighs the risk, or they think they can maintain a superior position such that the apprentice will never be able to kill them. Or they are invested in the continuation of the Sith as a whole, and believe that the strongest deserves to survive, even if that happens to not be them."

"How is your culture even still around?"

"Having the Emperor as an immutable capstone enables some degree of continuity, and the overall hierarchy is in general not seriously threatened by the actions of any one individual."

"But the population of the galaxy is only growing, whereas this makes it sound like yours can at best remain stable over the centuries—and it seems unlikely to do so, it would require long-term average replacement rate of one and that's very unlikely in this setup!"

"It has lasted several millennia thus far."

"Yes, hence my confusion."

"It is vastly more common to take an apprentice eventually than to not. Many take more than one, sequentially or in parallel."

"Huh. So killing your master just because you can is not that common."

"Depends on the Sith."

"Why did you not just leave?"

"To go where? I would have been pursued, certainly."

"Pursued? Why? If you had outgrown your master's teachings...?"

"An apprentice is an investment. You don't let one get away that easily."