Senran Kagura: A New Beginning

Akita is the son of a legendary shinobi named Askua. She mysteriously died while the father ran off, leaving him under the care of Katsuragi. With Ikaruga's help, she was able to raise Akita all throughout his life. They both try to have Akita live a normal life to worry less about his future, by disguising Katsuragi as his mother and Ikaruga as a nany of sorts. But he soon finds his real mother's scarf and, after some snooping, discovers a photo of Asuka with her shinobi squad, which included Katsuragi and Ikaruga. He encounters both of them about this, and they finally tell him the truth and realize that they soon have to make him a shinobi. Ever since then, he has been training to become a shinobi, just like his mother.