Hello Visionz,
If Player A's body said "I am with player B" then you can KOS player B as it is a valid KOS reason. I see.. is a little more complex as Player A could have looked at someone entirely different. If mainly depends on location of the body as if they were in a room with no windows or unbreakable windows then you can KOS player B but in an open area it is harder to determinate. If I was in your position I would place high suspicion on the player they were looking at if they were in an open area. Just use common sense and think about location when addressing situations like these.
I hope this answers your question.
Fell free to add me on steam
here if you have any more questions.