Description
Mamoru Aikawa has short curly brown hair, black eyes, and a stern expression. He typically wears a distinctive green fur coat with jeans.

His worldview formed after witnessing his father's suicide in childhood. His father left a note addressing "those who betrayed him," leading Mamoru to develop a doctrine: those who earn betrayal deserve death and should commit suicide. This stems from a deep fear of betrayal, driving his actions.

As a God Candidate, Mamoru commands thirty angels, the highest number controlled by any individual. He manipulates both masks and angels. His capabilities include avoiding angel attacks, measuring combatant strength levels, observing consciousness locations, and self-reinforcing physical attributes like strength and speed. He generates apostles by brainwashing humans, enhancing their abilities while placing them under his complete control, exemplified by converting Rika Honjo. Mamoru possesses extensive knowledge of the "God's Code" and the high-rise organ's mechanics, contributing to his cautious approach towards threats like the Railgun User.

Serving as a primary antagonist, Mamoru breaks the organ's established rules during critical confrontations. This leads to his execution by the Administrator amidst the battle between Sniper Mask and Rika Honjo. While dying, he releases Rika from brainwashing but leaves his apostle abilities intact. This act initially seems benevolent, but the Administrator reveals Mamoru's true motive: ensuring his doctrine's legacy by having someone embrace it willingly. Isolated incidents reveal perverted tendencies, such as burying his face in Yayoi Kusakabe's chest.

Relationships under his control include Rika Honjo as a brainwashed apostle and Yayoi Kusakabe among his angel subordinates. He dies defiantly, maintaining belief in his doctrine despite the organ's judgment.