Dimitri's Quirk is known as Devil Fox. It's a mutant type that came about from being tainted by Slaanesh's energy while he was in the womb. 

Enhanced Strength: Despite his lean and athletic build, Dimitri is quite strong being able to throw people or pieces of rubble with minimal effort. This strength also transfers to his tails, which are commonly used as weapons or barriers.

Enhanced Agility: Similar to a fox, Dimitri is quick on his feet and relatively slippery when fighting.

Enhanced Flexibility: Dimitri has been noted to be rather flexible an example being how he can do a perfect standing split or backbend.

Fox physiology: Dimitri possesses the abilities of a fox, namely his tails, night vision, and claws.

Pheromones: Dimitri has the ability to emit pheromones that mess with people and animals. His natural musk is a strawberry-scented odor that makes people not only hot and bothered around him, but makes him seem more approachable. Those with animal Quirks or any sort of enhanced smelling Quirk are affected much harder. (Think like poison ivy)
Sensory overload: Dimitri can make a concentrated pheromone that overloads the senses of anyone smelling it. It not only affects the sense of smell, but taste, touch, sight, and sound are enhanced to the point of sensory overload. 

Illusions: Befitting of a nine tailed fox, Dimitri can create illusions. He can create items such as furniture to trick people and even make himself look like someone else.

Foxfire: Dimitri can create and control blue fire. He can expel these flames from his mouth or project them from his body, usually in the form of wisps.

Prehensile tongue: Dimitri has a tongue that can get up to 8 inches long. It can also be barbed or bumpy.

Transformation: Dimitri can turn into a fox. He has two variants:
His "Mini" fox form can range from the size of a chihuahua to the size of a small horse.

His "Giant" form can range from equal to double Ryukyu's height in her dragon form. 

In addition to his Quirk, Dimitri is skilled in Martial Arts, Ballet, Pole dance, Gymnastics, Acro dance, and Aerial dance as his Quirk (and Slaanesh) drives him to be perfect in his movements.

In combat, he uses a double-bladed spear. His spear can split apart to become a pair of Eskrima sticks or the shaft can shrink to make them a pair of dual swords.