Kuroraimei

He is a demonic spirit in the form of a large black Zeraora and the main protagonist of Thunder Cat. He aims to be the most powerful ruler in the entire world due to his belief that humans and the Pokémon who live with them are causing chaos and suffering because of their "selfish" desires.

Physical Appearance
In life, Kuroraimei was a large black cat with thick fur and yellow eyes. He had a few battle scars from fighting with other animals and torn ears. He wore a rat's skull around his neck to indicate his association with his owner.

Upon permanently possessing the body of a recently deceased Zeraora, he becomes larger and more muscular, with a longer cat-like muzzle than most of his kind, thick black fur covering his entire body and piercing yellow eyes with slitted pupils that tend to change shape depending on his mood. There are two zigzagging yellow stripes on his forearms and another on each thigh. Unlike most individuals of his species, who have a tail-like bunch of fur extending from between their shoulders, Kuroraimei possesses an actual tail that protrudes from his rear end; the tail is very long, black in coloration, and resembles a lightning bolt. He also has light blue sclerae and small tufts of yellow fur on his chest; a larger tuft, which somewhat resembles a crest and can turn into a horn when he is angry, sits on his forehead almost directly between his eyes. His paw pads are also yellow and he has eight yellow lightning-bolt-shaped whiskers on each side of his nose, like a cat. Each of his hands has five clawed fingers (including a thumb), whereas each foot only has three clawed toes. His claws are all white and he has large ears with dark gray, almost black, insides.

Kuroraimei is able to shapeshift into a more demonic version of himself. In his new form, his fur is noticeably thinner and he appears to be more lean and well-muscled. He possesses nine tails and now somewhat resembles a saber-toothed cat. Jagged yellow stripes are now present on his body and he now has bright blue accents on his limbs, neck, and face. There are blue and yellow stripes on each tail as well; this makes him resemble a tiger.

His true form is a large black cat-like spirit with glowing yellow eyes and a jagged mouth, the inside of which is red. He has clawed hands and feet and spiky "fur" on his back and tail, which is noticeably shorter. He has three long scars across his throat, which are the marks of the animal who killed him.

Early Life
Kuroraimei was originally a black cat who lived with an old witch on the outskirts of Tamako City on an unknown world. Due to the superstition that black cats were cursed by demons (according to folklore, the color black was associated with evil), he and any other black cats who lived near the city were highly discriminated against by both humans and their pets alike. Kuroraimei, fed up with the constant mistreatment, decided to drink some of the red potion that his owner had concocted while her back was turned, gaining an increased muscle mass and a more aggressive personality, which prompted him to go out and pick fights with the animals in Tamako City. He emerged victorious in every fight, leaving his opponents viciously mauled, maimed, or in some cases, dead. When the witch found out that Kuroraimei had drunken from the potion, she cast the Permanent Nightmare curse on him and refused to feed him for the next five days as punishment.

Months later, the owners of the animals that Kuroraimei had attacked, who thought the witch had given Kuroraimei the potion deliberately, stormed her house to find her in bed, suffering from a terminal illness. When the man leading the group asked the witch for Kuroraimei's whereabouts, she told them that he'd fallen into the nearby river and drowned (which was a lie, as she was actually hiding Kuroraimei under her bed). Satisfied with this and the fact that the witch was dying from sickness, the owners left. After they'd left, the witch called Kuroraimei out of hiding and tried to slice his throat open with a sharp knife, only for him to realize she'd turned on him and escape into the city. Kuroraimei spent the next week hiding in the shadows by day and hunting by night to keep his strength up. During that time, the red potion's effects wore off, causing him to return to normal. He lived as a fugitive in the city until he was confronted by a group of seven cats, led by a white tom, who told Kuroraimei to leave the city permanently. Kuroraimei refused; a fight ensued, and in the end, his throat was sliced open by the white tom's claws, ending Kuroraimei's life.

Post-Death
Upon his death, Kuroraimei awoke in a dark, gloomy, afterlife known as the Land of Eternal Gloom, which he learned was the residence of the spirits of those who committed horrible crimes during their lifetimes. He met a wolf spirit named Akakiba and learned from her that he was indeed dead, and that since he was cursed, his ghost would soon find a suitable body to possess: the corpse of an unnamed Zeraora. Seconds later, Kuroraimei heard chanting in a language he didn't understand, causing him to panic. He then asked Akakiba who was chanting and what they were saying. Akakiba told him that she didn't know and wished him good luck before leaving. Panicking even more, Kuroraimei begged the wolf to come back, but was then immediately pulled from the Land of Eternal Gloom into what would become his permanent body. Upon the possessing the Zeraora's corpse, the white and teal fur turned black and the "ponytail" between its shoulders became an actual tail. Kuroraimei's eyes snapped open; needing air, he ripped open the plastic bag he was in and gasped in air, still unaware of his new form.

Chapter 1: An Unfamiliar World
Kuroraimei is surrounded by darkness, wondering where he is. The bed he's sitting on feels coarse and hard. He looks around the room and lets his eyes adjust to the gloom, noticing new-looking medical tools and many other things he's never seen before.

Coming soon.

Known Moves
Plasma Fists: A damage-dealing Electric-type attack where the user attacks with electrically charged fists. This move changes Normal-type moves to Electric-type moves.

Shadow Claw: A damage-dealing Ghost-type attack where the user slashes with a sharp claw(s) made from shadows. Critical hits land more easily.

Fury Swipes: A damage-dealing, multi-strike Normal-type attack where the user quickly rakes the opponent with claws or scythes two to five times in a row.

Telekinesis: A Psychic-type move where the user's psychic power causes the target float, making that target easier to hit for three turns.

Thunder Fang: A damage-dealing Electric-type attack where the user bites with electrified fangs. This move has a 10% chance of paralyzing the target and can also make the target flinch.

Outrage: A damage-dealing Dragon-type attack where the user attacks for two to three turns, then becomes confused.

Iron Tail: A damage-dealing Steel-type attack where the user slams the target with a steel-hardened tail. This move has a 30% chance of lowering the target's Defense stat.

Thunder Punch: A damage-dealing Electric-type attack where the user punches the target with an electrified fist. This move has a 10% chance of paralyzing the opponent.

Thunder Wave: An Electric-type move where the user launches a weak jolt of electricity and paralyzes the target.

Hex: A relentless, damage-dealing Ghost-type attack that deals massive damage to targets affected by status conditions.

Shadow Punch: A damage-dealing Ghost-type attack where the user throws a punch from the shadows. This attack never misses.

Blaze Kick: A damage-dealing Fire-type attack where the user kicks the target with a flame-cloaked foot. This move has a 10% chance of burning the target and critical hits land more easily.

Shadow Ball: A damage-dealing Ghost-type attack where the user hurls a shadowy blob at the target. This move has a 20% chance of lowering the target's defense stat.

Flamethrower: A damage-dealing Fire-type attack where the user scorches the target with an intense, fiery blast. This move also has a 10% of burning the opponent.

Aqua Jet: A damage-dealing Water-type attack where the user envelops itself in water and then lunges at the target with a speed that makes it almost invisible. This move always goes first.

Earthquake: A damage-dealing Ground-type attack where the user sets off an earthquake that strikes everything around it.

Aerial Ace: A damage-dealing Flying-type attack where the user confounds the target with speed and then slashes. This attack never misses.

More coming soon.

Chakra and Physical Prowess
Coming soon.

Skills and Abilities
Coming soon.

Quotes
Coming soon.

Trivia

 * In Japanese, his name literally means "black thunder". This is a reference to his fur coloring and his Electric typing.
 * Kuroraimei is cursed with the Permanent Nightmare spell, meaning his spirit would never get to rest after he died. The Permanent Nightmare was placed on him by his owner, who was a witch, when he was alive. When the witch died, Kuroraimei was cursed forever, as his owner, being the only person at the time who knew how to break spells as well as cast them, was dying from an unknown terminal illness. The curse also prevents Kuroraimei from being able to possess other living beings, thus permanently trapping his spirit within the Zeraora's body and forcing him to possess it.