It should not be like that - the area on the heat sink that directly touches the CPU is not circular, so the orientation matters. You can do it horizontally or vertically, but askew like that is something to avoid. The heat sink needs that contact and loose contact that's also not covering the entire CPU will make your temperatures worse. It's appears to be making good enough contact to not be a disaster (as in not having a heatsink at all), but that's a situation that should be remedied. Loosen up the connecting screws and rotate it and see if your temperatures improve. If not, the smart move is to remove it, reapply thermal paste, and attach it correctly.