Mirok, known in the original Japanese as Miroku, is one of the main protagonists of InuYasha: The Final Act. He is a young Buddhist monk of low rank, around eighteen years old, who travels the countryside performing exorcisms and demon exterminations to earn his living. His most defining trait is the hereditary curse inflicted upon his grandfather by the demon Naraku: a void called the Wind Tunnel, or kazana, in the palm of his right hand. This void can suck in anything that is not anchored, regardless of size or mass, making it a devastating weapon against demons. However, the curse is progressive; as Miroku ages, the Wind Tunnel grows larger, and if Naraku is not destroyed, it will eventually consume him just as it did his father and grandfather.

Because of this imminent death sentence, Miroku adopts a hedonistic and carefree attitude that contrasts with typical monk behavior. He often resorts to con artistry, fabricating supernatural threats in villages to secure food and lodging, and he has a notorious weakness for attractive women. He frequently asks any beautiful woman he meets if she will bear his child, claiming he wants an heir to continue his quest for Naraku if he should perish. His hands also have a habit of wandering, particularly toward Sango, a demon slayer who frequently punishes him for his groping. Despite these less-than-saintly flaws, Miroku possesses a core of genuine spirituality and serious resolve. When faced with real danger or when performing his religious duties, he is focused, brave, and deeply committed to protecting others.

His primary motivation is to defeat Naraku and break the Wind Tunnel curse, freeing his family line from its deadly legacy. He also seeks to avenge his forefathers and prevent the same fate from falling on any future descendants. In InuYasha: The Final Act, this drive intensifies as the final confrontation with Naraku draws near. Miroku's role in the group is that of a strategic fighter and spiritual support, using his staff for close combat and his Wind Tunnel to eliminate large groups of enemies or powerful foes when the opportunity arises. He also possesses additional spiritual abilities, such as using prayer papers for exorcisms and purifying barriers.

Key relationships shape his journey. He forms a close bond with Inuyasha, the half-demon leader of the group, and respects Kagome's spiritual strength. His most significant relationship is with Sango. What begins as one-sided flirtation evolves into a deep romantic partnership. In The Final Act, Miroku's feelings for Sango become sincere, and he struggles with the fear that his curse will prevent him from having a future with her. In the series' conclusion, after Naraku is finally destroyed and the Wind Tunnel disappears, Miroku marries Sango and together they have three children: twin daughters and a son. He continues to support his family by performing exorcisms with Inuyasha.

Miroku's development across InuYasha: The Final Act sees him confront his mortality and his reluctance to let others share his burden. He learns to accept help from his friends and eventually allows himself to hope for a life beyond the curse. His notable abilities make him a versatile and essential member of the group. The Wind Tunnel is his most powerful technique, but it requires careful management; overuse or damage to his hand can accelerate the curse's growth. He also relies on his monk's staff, physical combat skills, and a talent for sensing demonic energy. Miroku's blend of comic lechery, profound spiritual strength, and personal growth makes him a memorable and integral part of the story.