オスカー・ヴァイオレット

The biological father of Tesla and Nine with a PhD in engineering. He is the leading researcher of the Holy Grail's Fragment which possesses mysterious wave power. His expertise far surpass that of his mentor, Black Trader.

11 years ago, he became aware of the Fragment's hidden power and began researching on it. However, he lost his life in a fire accident at his house just before revealing his findings.