Im looking for this manga a read a while ago. Its about this girl(teenager) who is a ninja to the older man who is like a father(maybe also a love intrest) to her. She serves him in American (i think). Her actual father is the head of this ninja company and he's kind of mean to her...Anyway the girl's master dies in an explosion. And i think before her master died he told her that he wanted her to have a normal in japan. After the master dies she moves to japan and begins to start a normal life. there she meets this dude(in his teens or early 20's) who hires her

Oh I'm sure it's the same mangaka that did Vampire Knight. It's her new manga Shuriken to Pleats. Is it what you're looking for?

I'm in idol hell T.T

Yass thank you so much