I don't see it with Kol and Rebekah. To me they have a real sibling vibe. He annoys her and when she doesn't have her partner in crime (Nik ) to help with schemes she knows she can count on Kol for mayhem.

I know a lot of people see it as more like Kol loves Rebekah like she loves Klaus, but I don't really see it. They definitely have a bond like she does with Elijah, but I don't see it as a weird sexual connection the way she has with Klaus.