Normal: Looks like a human girl/princess. Sits on a giant throne with flowers. Being carried by many normal Cats.
Evolved: Now has color. Sits on a different throne with spikes. Being carried by darker Cats with tentacles. Strongly resembles Dark Emperor Nyandam. Now with colors.
KHM48 is available in the English version but is obtainable only via hacks. The English name and description are abc03104 and "abc03105 abc03106 abc03107" respectively. The awkward entry seems to be a result of no actual English text.
The unit's appearance tends to mimic that of Dark Emperor Nyandam. They both sit on a throne and point with a finger. The cats that carry the throne resemble the evil spirits under Nyandam's throne.
KHM48's name could be a reference to Japanese musical/idol group AKB48.