So! After a reallyyy long (embarrassingly long e.e) time writing about Aruka's biography, here it is! I put it in a spoiler cause it's actually kinda big, the reason I took this long was because I wanted to take the extra mile writing about some actual stuff Aruka lived in nin (a lot dramatized and a bit out of chronological order, but it makes sense in the story lol) instead of only having an in game reference of her in here!
TL;DR Aruka was born in a clan of healers, but had to learn to use poison to survive and create remedies in the ninja world, since she is bad at ninjutsu, taijutsu and genjutsu. After enduring the pain of loss of her team member multiple times, she learned to also use ninja tools to help protect herself and others. After a while, she went after forbidden means to be able to perform ninjutsu, which cost her health, but gave her much stronger power. Now she uses her strength to make sure sandies keep them selves safe in the wars that plague the ninja world!
One day I'll be able to draw like you guys do and have her drawn as a proper OC T-T