She is very determined whenever she does something. Once Satsuki has her mind set on something, nobody but Satsuki can talk her out of it.

Whenever she does something she gives her whole heart to it and isn't afraid to fight for those who can't.

Along with this, she is also stubborn as crap about something, which falls along with "Once Satsuki has her mind made up nobody can talk her out of it except for Satsuki herself" analogy.

Due to having to take care of herself as a kid, she has a naturally independent attitude and doesn't work well with most people.

She accepts help, but she has taught herself to stand on her own two feet if needed.