SOLVED. YA Manga - Ninja girl in a clan I think her name was Juniper or Juliette or something J

[Sara]

In the late 90s possibly early 2000s, I read a series or 4 or 5 manga that featured a ninja girl and her clan. I remember it was published in English-reading format, not Japanese reading format. The books were also larger and thinner than today's English manga format. They all had solid primary color covers with a picture on the front. I think the first one was either yellow or orange; there was green and purple and blue and red too, I think. The picture on the first one I think was the girl with a ponytail.

I think her name began with a "J". I thought perhaps Juniper or Juliette but I have tried Googling those with all sorts of other possible keywords and descriptions and no luck. I don't remember much of the plot except that there were more than one ninja clan and at one point she/her clan was having a tournament or some kind of battle with another clan *I think* in an arena inside a mountain. There was a big raised wooden indoors platform of sorts. Maybe her grandpa was the head of her clan; I don't remember.

[Sara]

I found it! In Powell's in Portland. It's "Juline."