Game of Thrones Begins to All Heavens

To put it simply, a modern young man traveled through time in Game of Thrones and became the illegitimate son of Daemontanklian. The protagonist has no interest in the throne and has no ambition to compete for hegemony. I just want to live a carefree life and see more. Go to more places. The protagonist is absolutely decisive in killing and does not rely on force. Never make a fuss when doing it.