Midou, Kaoru

Hikaru and Kaoru are two girls who, despite being younger than Hazuki, have been promised by their parents to marry Seiji and Kouhei respectively once they reach adulthood. Hikaru is engaged to Seiji, while Kaoru is engaged to Kouhei. Kaoru tends to be quiet and shy, and she can be a crybaby at times. However, despite her shyness, she can also be quite mean to Hazuki, which may possibly stem from jealousy because Hazuki lives with Kouhei.