I seem to have a habit of liking (or at least not disliking) all the Bioware companions everyone else hates. Ashley, Kaidan, Jack, Morrigan, Merill, Sten... I particularly like Jack, Morrigan and Sten.
I like Jack because from my point of view, she's the only Mass Effect team member who will make jokes at Shepard's expense (other than the dancing), and who doesn't wait for him to threaten her species/join a terrorist group/cheat on her to stand up to him. Probably one of the best examples of this can be found in the Citadel DLC from ME3, after she says she has a surprise for Shepard.
Shepard: "...This isn't what I was expecting."
Jack: "That's why it's called a surprise, dumbass."
And Morrigan, well, as deeply unpleasant as she is it's really understandable why she's like that. If you do go out of your way to befriend or romance her as a non-evil character, you get some really heart warming responses.
As for Sten... I kind of had a big breakthrough with this character because of one piece of advice I read from someone on how to get approval from him. "If you think he's wrong, call him out on it. Stand up to him." And whenever I've followed that advice, it's worked. That just makes me really respect his character, the fact that someone who seems so inflexible and stubborn respects it when people stand up to him. I don't think there's much more to it than that.
Oh, and Sten has a wicked sense of humour sometimes:
*After Morrigan has repeatedly brought up the idea of her and Sten having sex in order to tease him*
Morrigan: "You seem so deep in thought, my dear Sten. Thinking of me, perhaps? The two of us together at last?"
Sten: "Yes."
Morrigan: "I... What did you say?"
Sten: "You will need armour, I think. And a helmet, and something to bite down on. How strong are human teeth?"
Morrigan: "How strong are my teeth?!"
Sten: "Qunari teeth can bite through leather, wood, even metal, given time. Which reminds me; I may try to nuzzle."
Morrigan: "NUZZLE?!"
Sten: "If that happens, you'll need an iron pry-bar. Heat it in a fire first or it may not get my attention."
Morrigan: "...Perhaps it would be better if we did not proceed."
Sten: "Are you certain? If it will satisfy your curiousity..."
Morrigan: "Yes! Yes, I think it is best."
PS.
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