Primary

• Kaoru Nakanishi Friend of Kouichirou Ogata

Extended

• Kouichirou Ogata Friend of Kaoru Nakanishi
• Kouichirou Ogata Step-brother of Mio Ogata
• Kouichirou Ogata Son of Hajime Ogata
• Kouichirou Ogata Step-son of Minatsu Ogata
• Kouichirou Ogata Best friend of Masanori Shinozaki