I actually like Astarion, which is partially why the intro bugs me. If he didn't try to kill me, I would gladly bring him along and even when I find out he's a strange vampire spawn, I'd maybe think of trying to help him except he again tries to kill me by almost biting me in my sleep.

Consequently, Sebille in DOS2 is the ONLY origin character I rejected immediately. Why? She put a needle to my throat. Why would I want to take her with me? The narrator even says I'm not sure how I'm going to sleep with her around.