Gremmy Thoumeaux

is a Quincy and a member of the Wandenreich's Sternritter with the designation "V" - "The Visionary".

Appearance
Gremmy has a child-like appearance, with messy light-colored hair and youthful features. His attire is a variation of the Sternritter's typical white uniform, consisting of a loose trench coat featuring a hood and a high collar.

Personality
Gremmy takes delight in his power and believes imagination to be the greatest force in the world. He can be cruel to those created by his power, mercilessly killing Guenael Lee. He also is quite arrogant, believing himself to be the strongest Sternritter. He is incredibly proud and confident in his own abilities, declaring that Kenpachi Zaraki cannot comprehend his abilities until he loses, he then declared that he could defeat him without even using a finger despite knowing how powerful his opponent is.

The Thousand-Year Blood War arc
When Guenael rises after being struck by 11th Division Lieutenant Yachiru Kusajishi, Gremmy makes a deep cut in his shoulder. Sitting inside the barrier which is healing 3rd Division Captain Rōjūrō Ōtoribashi and 9th Division Captain Kensei Muguruma, he tells Guenael he's only a product of his imagination and he will now vanish from his mind. After disposing of Guenael, Gremmy reveals he has killed the two captains, shocking 4th Division Lieutenant Isane Kotetsu. Dodging an attack from Yachiru, he imagines the bones in her hand being made of cookies, effectively making this true. He goes on to explain his powers, but he is interrupted by the arrival of Captain Kenpachi Zaraki.

Gremmy takes note of Kenpachi's strong appearance, and raises the ground to make a "stage" for he and Kenpachi to fight on. He explains his power to Kenpachi, who only tries to attack. As Gremmy tries to explain why Kenpachi can't cut him, Kenpachi presses on and slashes through part of Gremmy's right shoulder. Gremmy remains silent as Kenpachi explains that Gremmy can't imagine something that he can't cut.

Gremmy gets up, revealing he imagined himself healed. He declares that he will kill Kenpachi through his imagination without even lifting a finger. He suddenly makes lava appear to kill the captain. When Kenpachi tells Yachiru to get away he says she can't and then explains cookies to Kenpachi. He goes on to submerge Kenpachi in water and then throw him into a fissure which he then closes, stating that Kenpachi will drown within an hour. Kenpachi then breaks free and is attacked by Kenpachi and successfully blocks him.

Powers and Abilities

 * Gremmy has the ability to turn fantasy into reality. For example, if he imagines that the bones in someone's arm are made of cookies, this will become true. By imagining that his body is "more sturdy than the strongest steel," he can drastically increase his defense. He can even create living beings using this power, having created Guenael Lee and then erasing him from existence with the same power. If Gremmy shifts his attention away from the target, it can revert to what it was before. Using this power Gremmy can also create elements and substances from his mind, creating lava, water and even creating a gigantic stone platform and steel pillars to attack and defend against opponents and manipulate them as he sees fit.

Hirenkyaku Expert: Gremmy is fast enough to effortlessly dodge a surprise attack from a Shikai-wielding Yachiru Kusajishi, a lieutenant renowned for her speed, despite the fact that her Shikai is also very difficult to dodge. Gremmy then easily grabbed her hand mid-swing, preventing her Shikai from using its preemptive strike to harm him.

Infiltration Expert: Gremmy was able to penetrate Isane Kotetsu's barrier and kill two incapacitated captains, only being noticed when he took action against a fellow Sternritter. Even Yachiru Kusajishi, an expert in infiltration in her own right, failed to detect him.

Quotes

 * (To Yachiru Kusajishi) "The most powerful force in this world is 'imagination.' Anything I imagine... anything at all... becomes reality."