Hamasaki Noire's Links
Being able to focus on taking care of someone in her childhood and giving him the love she craved was theraputic in a way. She's always been very motherly to him despite their two year age gap. They had such a strong bond that when it was time for her to live on campus due to safety issues- it was really difficult for the both of them. They ended up frequently visiting each other on campus and she showed him around. In a way, this was her saving grace and she felt guilt having to leave him behind. Once he had gotten into UA, they couldn't spend too much time together because they were both busy now but their care for each other is very strong. Whenever one has a problem, they'll go to the other for comfort.
He feels a very deep rooted devotion to her. She helped him when he was in a bad place even though she wasn't doing well herself. Her selflessness in their childhood and protection/acceptance of him as her brother despite their situation really changed him. His main goal in life is to protect her as she did him.