Super Mouse

Super Mouse (超マウス, Chō Mausu) was a member of the Monster Association. He was a Demon-level monster who briefly appeared to fight Garou alongside Showerhead and Unihorn. He was killed by Overgrown Rover.

Appearance
Super Mouse was an anthropomorphic mouse with white fur and a very muscular body. He was taller than Garou and had a long ringed tail. Similarly, his hands and feet also had ringed linings across them. Super Mouse also had featureless eyes with no irides and pupils, having a white sclera instead.

Personality
Super Mouse was rather confident in his abilities and sadistic. However, he acknowledged the strength of stronger Dragon-level mysterious beings and was willing to work alongside other monsters when fighting opponents.

History
Prior to him joining the Monster Association, Super Mouse was a lab mouse who was constantly experimented on. As a result, his body became mutated and he gained increased strength, speed, stature, and limited regeneration. Sometime later, he would come to join the Monster Association and work together with Unihorn and Showerhead.

Monster Association Arc
While Garou and Tareo were walking away from Overgrown Rover, Super Mouse appeared alongside Unihorn and Showerhead and attacked Garou. Super Mouse deemed Garou a warm up before the fight against the heroes. Showerhead and Unihorn attacked Garou with their respective techniques, but Gaoru easily dispatched both of them. Super Mouse threw a left jab at Garou, but the Hero Hunter blocked his punch using the Whirlwind Iron Cutting Fist, creating several wounds. The monsters, however, get back up, and express surprise at Garou's superb fighting strength as they have been all evaluated by Gyoro Gyoro to be demon level threats.

Garou is scornful of such arbitrary labels and declares himself a Dragon-level monster. Super Mouse scoffs at the notion, stating only the upper echelon of the Monster Association were at that level of strength. The three monsters then prepare their special combo they developed called the Demon Trinity Bursting Speed Thrust. However, Garou already experienced a similar technique against Stinger, and is able to easily deflect the attack and Unihorn behind him. Unfortunately, the attack inadvertently hit Overgrown Rover. In anger, the monstrous dog fires an energy blast at everyone in the hallway. Showerhead attempts to stop the attack with his maximum water pressure, but he is vaporized alongside Unihorn. Super Mouse is confident that his regeneration can revive him, although the energy blast overwhelms him, and he meets the same fate as his comrades.

Abilities and Powers
Being a Demon-level mysterious being, he was a strong fighter, and was able to take some blows from an evolving Garou. However, he was completely helpless against Dragon-level monsters like Overgrown Rover and was obliterated by just one of the dog's energy blasts.

Physical Abilities
Immense Strength: Super Mouse boasted impressive physical strength, and was able to shatter walls with complete ease.

Immense Speed: Being a Demon-level monster, Super Mouse had a high level of speed and was able to relatively keep up with an evolving Garou.

Regeneration: Due to his time being experimented on as a lab mouse, he gained a limited degree of regeneration and was able to quickly regenerate from Garou's attacks. His regeneration has a limit, and this was seen when he was killed by Overgrown Rover's blast.

Fighting Style
Proficient Hand-to-Hand Combatant: Super Mouse fought mostly as a hand-to-hand combatant.
 * Combination attack: Triple Demon (三鬼ー体, Miki ̄-tai) Blasting Speed Thrust (爆速刺し, Bakusoku-zashi): The attack utilizes the powers of Unihorn, Showerhead, and Super Mouse. Super Mouse launches Unihorn forward as Showerhead continues to propel him with Jetstream. The attack is powerful enough to severely anger Overgrown Rover although Garou found it slow and compared it to Stinger's attack.

Trivia

 * Bomb would have beaten Super Mouse in one swift attack before the monster could even react.