Cementoss

Overview

Cementoss, whose real name is Ken Ishiyama, is a Pro Hero and a faculty member at U.A. High School in My Hero Academia. Within the school, he serves as the teacher for Modern Literature and oversees Quirk training sessions. Capable of manipulating concrete at will, he acts as an indispensable defensive powerhouse, particularly during engagements in urban areas. Calm and reliable, he plays a key role in both educating young hero students and managing campus infrastructure.

Appearance

Cementoss is characterized by his large physique, grey skin, and a highly distinct, rectangular block-shaped head. Hair grows from the back of his head, which he keeps tied up in a bundle. He typically maintains a stoic countenance with minimal facial expressions.

Personality

Despite his rigid and intimidating silhouette, Cementoss possesses a gentle, composed demeanor and remains completely unshakeable regardless of the situation. He is deeply committed to his duties as both a hero and an educator. He is also a fan of All Might. In contrast to his own blocky appearance, he has a personal fondness for rounded objects and manjuu, even establishing a club dedicated to seeking out perfect circular shapes.

Abilities

His Quirk, known as Cement, allows him to alter the viscosity of any concrete he touches and freely reshape it. He can soften concrete into a fluid state or instantly erect dense walls and barriers. When operating in concrete-rich environments, his power offers practically infinite resources and exceptional defense, though his abilities are severely limited in natural settings like forests or mountains. One of his signature techniques is Hajotsui.

Background

Originally from Yamagata Prefecture, Cementoss serves as a Pro Hero and teacher at U.A. High School, where he has also contributed to designing training facilities. During the USJ incident, he responded as part of the reinforcements and erected a protective barrier to shield All Might when the latter exhausted his transformed state. At the U.A. Sports Festival, he handled stage construction, repair, and served as a referee. In later conflicts, he joined the assault on the Gunga Mountain Villa, battling Geten to a double knockout, and later helped construct and repair the flying fortress known as the Coffin in the Sky during the final war.

Relationships

He works alongside fellow U.A. faculty members such as Shota Aizawa, Midnight, and Present Mic to educate students and maintain school security. During the practical final exams, he tested students Eijiro Kirishima and Rikido Sato, overwhelming their direct assaults. In the Paranormal Liberation War, he engaged in a intense fight against Geten of the Paranormal Liberation Front. During the final battle, he collaborated closely with students like Momo Yaoyorozu and Mei Hatsume to maintain damaged infrastructure in real time.

Trivia

Cementoss proposed the concept for the TDL training facility at U.A. High School. Driven by his love for smooth contours, he also founded a personal club centered around finding perfect circles.