The only reason why I came to this conclusion is because of the slide in the previous chapter when he has a flashback of his family. That made me think.
I feel like it's reasonable to say that Sasuke was teamed up with Karin as long as he was teamed up with Sakura. It was clear to him that they both liked him and he found them both annoying. However, when left the village he didn't kill Sakura, he just put her in a genjutsu, and he did it again in this situation. For Karin, he killed her with no sympathy.
At first I saw it as pity since Sakura was weaker than him, but Karin is weaker than Sakura so I would have expected a similar faith for both of them.
Overall, I only came to this conclusion because of the contrast between how he treats Sakura and how he treats Karin. With his rinnegan, he could have easily killed Sakura and he clearly has no liking for Team 7 since he wants to kill Naruto. He killed Karin without regret and didn't even have her in his mind after that. Idk, that's just what I've been thinking of so far