Mind control through telepathics works a bit like reaper indoctrination in Mass Effect … if you just brute force into someone’s mind it will do a lot of damage and the subject will probably not retain useful for long (Unless you want to keep them as a literal puppet to micromanage).

If you start subtly, on the other hand, and slowly and patiently work your way on from there they might not even see it happening until it is too late … and by that time they’ve internalized your will enough that they can still act independently within that frame. It is an incredibly devious thing to do to someone, but luckily also far above most mages’ capabilities.

Ki’i’mar has obviously started this a long time ago for poor Na’Ki … what we see here is her closing the bag with a final push.

↓ Transcript
Na'Ki: I ... I did what I thought was right ...
Na'Ki: <thinking> ... did I?
Ki'i'Mar: Yes you did. And I am PROUD of you.
Na'Ki: I ... I am still here to serve you ... Mistress.
Na'Ki: <thinking, but it gets weaker> Didn't you see what she just did to the captain?! This is wrong!
Ki'i'Mar: I know. But I need ABSOLUTE DEVOTION from you.
<Na'Ki closes her eyes as the Gena toucher her face>
Na'Ki: <thinking, but the last bits get finally washed away by the Gena's voice> Do something! Don't let her ...
Ki'i'Mar: You are going to be a PERFECT SERVANT. Maybe even BETTER than Maq.
Ki'i'Mar: Now tell me ONE THING, Na'Ki: WOULD YOU DIE FOR ME?
<Na'Ki kneels in front of her>
Na'Ki: ... yes, Mistress.