Primary

• Kota Furuya Older Brother of Ryuuji Furuya
• Kota Furuya Older Brother of Ouzou Furuya

Extended

• Ryuuji Furuya Younger Brother of Kota Furuya
• Ryuuji Furuya Older Brother of Ouzou Furuya
• Ouzou Furuya Younger Brother of Kota Furuya
• Ouzou Furuya Younger Brother of Ryuuji Furuya