A Strange Orbiting Object

What is 200 kilometers in diameter, located outside the plane of the solar system, and orbits the sun is a direction opposed to everything else in the solar system? Your guess is really as good as anyone else's at this point since scientists are baffled.

This trans-Neptunian object (TNO) is the subject of a New Scientist article that reports on recent findings from the Pan-STARRS 1 Outer Solar System Survey.  The paper associated with this discovery (titled "Discovery of A New Retrograde Trans-Neptunian Object: Hint of A Common Orbital Plane for Low Semi-Major Axis, High Inclination TNOs and Centaurs") labels the newly discovered NTO "Niku" (Chinese for "rebellious").

The article goes on to ponder the cause, be be it billiards among the planets or the mysterious Planet Nine. Just a quick hint - Planet Nine is not a suspect.

It seems we have plenty more to discover about our neighborhood. Who says there's nothing new under the sun (or orbiting it)?