In the recent animated adaptation of the events of the third Tekken game, taciturn Jin Kazama is featured as the main character.
Jin himself is the son of Jun Kazama, a female karate master of composure and benevolent nature, and Kazuya Mishima, a pugnacious and violent karate master whose father in turn is the even more corrupt CEO, Heihachi Mishima.
As such, Jin being raised by his gentler mother develops a much more gentle personality.
A demonic entity, named Ogre, shows up and promptly kills his mother, which Jin understandably is traumatised by. Moreover, she implores him to seek out his paternal grandfather, Heihachi Mishima.
Thus, Jin’s pronoun - in the Japanese dub - is from the onset of the series, boku, and he only switches to ore in the middle of episode 2, after being immersed in the hard training at the hands of his stern grandfather, Heihachi, – presumably as a mark of him also maturing. The boku could be seen as a remnant of his upbringing with his mother, a Kazama, where it reflects his gentler nature and the ore, his father’s Mishima heritage, but also the fact that he is repeatedly told by Heihachi to firmly engrain the values and teachings of Mishima into his very self.
When Heihachi, his paternal grandfather, questions about his reason for seeking him:
“All of a sudden, the thing came and killed my mum. I don’t care whether or not you are gonna help me, I will absolutely track it down!” (English translation is my own)
Boku is used here by him prior to his training with Mishima and anta underlines a less polite variation of anata, showing his frustration towards his paternal grandfather – having not shown much hospitality when Jin has barely survived against from the monster, and his mother sacrificed herself to blow it up.
Elsewhere boku resurfaces when he talks to an old friend of his. Ore is otherwise his main go to pronoun in terms of projecting the more mature/hardened persona of his.