Complex sentence: It turns out that he was adopted by the Kagura Clan, and his real parents were murdered, and for those fifteen years, Tatsuo was hunting for the mastermind, who manipulates all industry, finance and even politics.
Split into simpler sentences: It turns out that Tatsuo's parents were murdered and he was adopted by the Kagura Clan. For fifteen years, Tatsuo has been hunting for the mastermind, who manipulates all industry, finance and even politics.