Mikk, Tyki

ティキ・ミック

Shortly after Allen meets Arystar and recruits him as an ally, he encounters Tyki. The man leads a double life: his "white side" is a carefree, goofy man of Portuguese descent who travels with humans who love playing poker, while his sadistic "dark side" has a lust for blood and assumes his role as Noah's descendant (and thus, one of the antagonists).
Tyki and his group trick Arystar into a game of strip poker, winning literally all his assets, but Allen interferes and plays against them. He wins (using cheating techniques learned from years spent with Cross), and Tyki gives him a pack of playing cards before his group departs.
The author provides the first hint that something is wrong when the group is revealed to possess a chunk of silver bearing the name Kevin Yeegar—the name of the exorcist general who had recently been killed. In their next encounter, Allen meets Tyki's Noah side, and, after a conversation, Tyki leaves him to die from a heart wound inflicted by Tease (a flesh-eating type of golem in the form of a butterfly) after destroying his Innocence, spreading the same cards he had given Allen over the boy's body. After realizing that Allen's name would not come off the walls of the jail cell, he goes with Jasdero and Debit to find Cross.
Tyki's powers stem from his ability to selectively interact with his surroundings. This allows him to become effectively intangible, passing through all manner of matter as a ghost would, or walking on air.
His powers also have an offensive aspect, allowing him to phase his hand into his opponents' bodies and selectively interact with their organs (i.e., the heart), crushing them or tearing them out without leaving any external wounds.
He also possesses the ability to reject the existence of space around an area he chooses, which essentially makes it possible for him to create a vacuum around anything he pleases (this ability was put to good effect against Allen, which allowed Tyki to suffocate him in their fight).
He usually attacks using his powers in concert with the flesh-eating Tease golems given to him by the Earl of Millennium. The Tease themselves are capable of multiplying themselves, becoming a large swarm to consume Tyki's enemies, or changing shape to act as shields or throwing blades.
He was responsible for the death of Kevin Yeegar, one of the 5 exorcist generals, and has killed over 6 other exorcists himself, including Suman Dark (whom Allen had tried to save), Tina Spark, Gwen Frere, Sol Galen, Kazanna Reed, Chakar Rabon, and Daisya Barry.