Why does the Sun rise in the west on Pluto?

The premise that the Sun rises in the west on Pluto is correct. This phenomenon occurs because Pluto exhibits retrograde rotation, meaning it rotates on its axis in the opposite direction of the Sun and most other planets in the solar system.1

Pluto’s axis of rotation is tilted at an angle of 120° from the perpendicular to its orbital plane, causing its north pole to point 30° below the plane. Because of this extreme axial tilt and its retrograde rotation, an observer standing on the surface of Pluto would see the Sun rise in the west and set in the east.1