Shota & Eri

Although Aizawa is very serious, he is really fond of Eri. They have father-daughter relationship.

Since Eri was saved, Aizawa took care of the little girl, helping her emotionally and with her quirk

Eri is a girl in Boku no Hero Academia whose tragic past makes her one of the most important characters in the series. She is the granddaughter of the boss of the Shie Hassaikai yakuza group, but after her parents abandoned her out of fear of her power, she fell under the cruel control of Overhaul (Kai Chisaki), who exploited her for his experiments.

Her Quirk is called Rewind, an extraordinary ability that allows her to reverse a living being’s body back to a previous state. This can undo injuries, remove mutations, or even cause someone to disappear if rewound too far. Because it’s so unstable, Eri has trouble controlling it, and for most of her life it has been more of a curse than a gift. However, with training and guidance, she begins to learn how to use it to help others, such as when she saved Izuku Midoriya during his fight against Overhaul.

Physically, Eri is a girl with pale skin, large innocent red eyes, and long, silvery-blue hair that falls past her waist. Her most distinctive feature is a small horn on the right side of her forehead, which grows or shrinks depending on how much power she builds up.

Personality-wise, Eri is shy, quiet, and initially very fearful due to years of abuse. She struggles with guilt, believing herself dangerous to those around her. Yet, under the care of Class 1-A and Pro Heroes, especially Mirio Togata and Izuku, her kind, gentle, and curious nature slowly shines through. At heart, she is sweet and compassionate, yearning to experience the normal childhood she was denied.

Aizawa Shota, also known by his hero name Eraser Head, is a pro hero and a teacher at U.A. High School, where he trains aspiring heroes. He's known for his strict and logical approach to teaching, valuing results and practicality over flashy appearances.

His quirk, Erasure, allows him to nullify another person's quirk just by looking at them. However, the effect stops if he blinks or if his line of sight is broken, making it a quirk that requires focus and physical stamina. He also uses a special scarf in combat to restrain enemies while their quirks are disabled.

Aizawa has a slim, tall build, with long messy black hair and tired-looking black eyes. He usually wears a black outfit with a capture weapon scarf and often looks like he hasn’t slept in days. Despite his disheveled appearance, he's highly skilled and intelligent.

His personality is serious, calm, and blunt. He rarely shows strong emotions and prefers to observe and act only when necessary. Though he seems cold, he deeply cares for his students and will go to great lengths to protect them.

In the world of My Hero Academia, U.A. High School (short for U.A. High) is the most prestigious school in Japan for training future professional heroes. Located in Musutafu, this elite academy is famous for its high standards, powerful teachers, and exceptional students. It offers various departments, but the most well-known is the Hero Course, where students learn to use their Quirks responsibly and effectively in real combat situations.

To enter the Hero Course, students must pass a highly competitive entrance exam, which typically involves physical trials and rescue scenarios that test both strength and judgment. Only a small number of applicants are accepted each year, making admission a major accomplishment.

U.A. is also home to other departments, such as the Support Course (for creating hero gadgets), the General Studies Course, and the Business Course. Each plays a role in the broader hero industry.

The school is known for its unique teaching methods. For example, students participate in dangerous, realistic training exercises like the U.A. Sports Festival and simulated villain attacks. The goal is to prepare students for the threats heroes face in real life.

U.A. also employs top Pro Heroes as instructors—like Shota Aizawa (Eraser Head) and All Might, the Symbol of Peace—who offer expert guidance and mentorship.

More than just a school, U.A. represents hope for society, raising the next generation of heroes in a world where villain activity continues to rise.

the world of My Hero Academia, a Quirk is a unique, superhuman ability that most people are born with. About 80% of the global population has a Quirk, and no two Quirks are exactly alike, although some may share similar traits. Quirks typically manifest around the age of four and are influenced by the abilities of one's parents, though they can combine or mutate into something completely new.

Quirks can range from simple powers—like generating fire or manipulating ice—to more complex ones like teleportation, super strength, or even the ability to erase other Quirks. Some are passive and affect the user’s body or senses, while others are active and must be triggered. People without Quirks are called Quirkless, and they are a small minority, often facing social discrimination.

In society, Quirks play a major role in shaping careers and personal identity. Some people use their powers to become Pro Heroes, licensed individuals who protect civilians and fight villains. Others may use their powers illegally, becoming villains.

While Quirks are powerful, they often come with drawbacks—such as physical strain or strict limitations. Mastering a Quirk takes training, discipline, and understanding its strengths and weaknesses.

Quirks are central to both the story and characters of My Hero Academia, driving the action, challenges, and dreams of heroes in training.