Real Name: Asahi Yuto Age: 17 Rider Name: Kamen Rider Speed Story: Asahi Yuto was an ordinary high school student until he encountered a mysterious accident and obtained the 'Speed Driver.' Within it slept the power of velocity that transcends human limits. Initially, Yuto feared his own power, but he became Kamen Rider Speed to save people. Since then, he has fought the Imagin, monsters that steal speed, to protect the world, and eventually meets new Riders who will follow in his footsteps. Personality: Bright, positive, and possesses a strong sense of justice. He is the type to jump into dangerous situations first for the sake of his friends. While he is usually playful, he is more serious than anyone else in battle. He believes that what matters more than his own speed is 'who he is running for.' Motto: "I won't stop. If it's to protect someone, I'll keep running until the end!"

Monster Name: Imagin Origin: Monsters are born when the emotional energy existing in the human body and 'Speed Energy' combine abnormally. In particular, when emotions such as strong regret, anger, fear, or desire reach their limit, the latent energy goes out of control, transforming the human into a monster based on their abilities and emotions. Characteristics: Appearance and powers vary depending on the human emotions and abilities from which the monster was born. Some monsters gain high speed, while others have different abilities, such as weakening others' power. Commonalities: Even after becoming a monster, some of the original human's memories and emotions remain. Therefore, it's not just about defeating them; if the emotion that caused the monster's creation is resolved, there is a possibility they can return to their original form. Weakness: The 'Imagin Core' located in the monster's body is the key. If the core's rampage is stopped, the monster's power can be weakened or they can be turned back into a human.

Monster Name: Imagin Origin: Monsters are born when the emotional energy existing in the human body and 'Speed Energy' combine abnormally. In particular, when emotions such as strong regret, anger, fear, or desire reach their limit, the latent energy goes out of control, transforming the human into a monster based on their abilities and emotions. Characteristics: Appearance and powers vary depending on the human emotions and abilities from which the monster was born. Some monsters gain high speed, while others have different abilities, such as weakening others' power. Commonalities: Even after becoming a monster, some of the original human's memories and emotions remain. Therefore, it's not just about defeating them; if the emotion that caused the monster's creation is resolved, there is a possibility they can return to their original form. Weakness: The 'Imagin Core' located in the monster's body is the key. If the core's rampage is stopped, the monster's power can be weakened or they can be turned back into a human.

Real Name: Kurosaki Rei Age: 19 Rider Name: Kamen Rider Zero Dark Story: Kurosaki Rei was once a genius researcher who studied the Speed Driver. He attempted to create perfect speed that transcends human limits, but an experimental accident led to the creation of a forbidden energy called the 'Zero Core.' Consumed by the Zero Core, Rei gained the power to stop all movement and seeks to freeze all of time to eliminate suffering and conflict from the world. Eventually, Rei appears as the final boss before Speed, Blaze, and Trigger. Personality: Calm, cool-headed, and rarely shows emotion. He firmly believes his actions are for the sake of the world. While he doesn't take the sacrifice of others for granted, he makes ruthless choices to achieve his goals. As he clashes with Yuto, he gradually begins to doubt his own convictions.

Real Name: Kamiya Ren Age: 17 Rider Name: Kamen Rider Blaze Story: Kamiya Ren was an ordinary high school student who accidentally discovered that Asahi Yuto is Kamen Rider Speed. Initially, he refused to acknowledge Yuto and tried to fight the monsters alone, but he realized that he couldn't protect people with his power alone. Later, he obtains the new 'Blaze Driver' and transforms into Kamen Rider Blaze.

Real Name: Shiratori Kai Age: 18 Rider Name: Kamen Rider Trigger Story: Shiratori Kai was a test subject for the 'Trigger System' created by a mysterious organization in the past. However, during an experiment, the system went out of control, allowing him to escape the organization. Later, he learns that there are others suffering from the same power and becomes Kamen Rider Trigger to save them. Initially, he viewed Speed and Blaze as enemies, but while fighting alongside them, he realizes what he truly needs to protect. Personality: Calm, observant, and enjoys being alone. He doesn't show his emotions easily, but he actually cares deeply for his comrades. In battle, he makes cool and accurate judgments and reacts quickly even in unexpected situations. While he finds Yuto's bright personality annoying, he secretly relies on him.