Prince Neko and his mom both have marks on their foreheads: Prince Neko has four small dots surrounding a big circle, symbolizing his connection to the Five Worlds from his home in the sun; his mother the Queen has three ovals over a crescent moon, symbolizing how she comes from a different galaxy. Prince Neko’s father, Aurinko, doesn’t have any marks—foreshadowing that he isn’t devoted to either the Five Worlds or his old galaxy.
Speaking of Aurinko, notice that his strange black fabric mask covers both his eyes. It represents how blind he is to the truth.
And as Stan Moon, the Mimic (AKA Aurinko) has the same markings as Prince Neko, only the big circle (representing the sun) has a hole in it. This represents how he's pretending to act in the best interest of the Five Worlds, but is actually working toward his own selfish goal.