Oneself, Myself, I
pronoun, の adjective
The kanji and the word are exactly the same. That means they share meanings as well. It also means myself and I.
おのれ
As for myself? I'm not Bob. oh no, Ray (おのれ), Ray is my name.
俺は、みんな死ぬ前に己の墓は己で建てるべきだと思うけどね。
I think people should build their own graves before they die.