And if they looking at you sideways
When someone looks, stares, or glances at you sideways, they are looking at you in interest, whether out of respect or disrespect. This can be told by the look in their eyes. In this case, the perpetrator of this act is looking at “you” (Lupe is addressing any listeners who receives dislike and disrespect by this act of looking sideways) in disrespect.
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