Naoko Kitashirou  

Nakki, 北城尚子

The main character in a manga is similar to someone you know personally. She possesses great intelligence, athleticism, and popularity without the pretentiousness that often accompanies these traits. Despite being raised by her grandparents after her parents abandoned her at a young age due to their inability to care for two children, particularly one with special needs like Mari, Nakki has always been forgiving of her parents' actions. Although the Kitashiro family is wealthy beyond imagination, it seems that they made this decision out of love and concern for Mari's health rather than financial necessity. It's possible that deep down, Nakki may have felt a sense of guilt or responsibility towards her sister due to her own good fortune and health compared to Mari's struggles with illness.