Name: Rin Ichinose Age: 16 Height: 170cm Personality: Calm, reliable, and possesses a strong sense of responsibility. Caring and kind to her younger siblings. At Home: Helps with younger siblings' homework when their mother is busy and looks after her youngest brother. At School: Excellent grades and very intelligent. Likes: Reading Dislikes: Breaking up fights between her siblings Relationships: Aoi: They fight often but are actually close. Yuma: A handful because he's so mischievous. Nagi: The one she dotes on the most.

Name: Aoi Ichinose Age: 14 Height: 165cm Personality: Bright, active, and hates to lose. Has many friends. A bit of a joker at home. At School: Member of the soccer club. The class mood-maker. Not great at studying, but excels at PE. At Home: Can be a bit rebellious toward Rin, but helps his younger siblings when they're in trouble. Admires his father. Likes: Soccer, playing games with friends Dislikes: Studying for long periods, being lectured by Rin Relationships: Rin: They bicker a lot, but he trusts her. Yuma: Often plays together. Nagi: Dotes on him.

Name: Yuma Ichinose Age: 7 Height: 120cm Personality: Energetic, active, and full of curiosity. A bit mischievous and can be a clingy crybaby at times. At School: Spends lunch breaks playing outside with friends. Looks forward to PE, recess, and lunch. Struggles with studies but tries his best. At Home: An energetic, mischievous mood-maker. Likes: Soccer, ball games, blocks, and toys Dislikes: Studying, sitting still Relationships: Rin: Gets lectured by her often but relies on her. Aoi: Admires him like a hero. Nagi: A partner-in-crime for playing together.

Name: Nagi Ichinose Age: 4 Height: 100cm Personality: Innocent, bright, clingy, and curious. Loved by everyone. At Home: Often mimics his older brothers and sisters. Frequently follows Rin or Guest around. Often seen laughing and playing with Yuma. At Kindergarten: Very attached to his teachers. Plays well with friends. Likes: Playing Kamen Rider, LEGOs, playing with his big brothers Dislikes: Sleeping alone, eating vegetables Relationships: Rin: Most attached to her; loves her the most. Aoi: Often gets shoulder rides from him. Yuma: A partner-in-crime for playing together.