Shigen Amawaka (天若 止弦) was the eighth head of Amawaka House and the biological father of Seigen Amawaka. He was also the paternal grandfather of Mayura Otomi.
Shigen resembles his son Seigen Amawaka, with the prominent Amawaka yellow hair streak. The only difference is that he was older with heavy wrinkles.
Shigen had a distorted personality.
He was quite ruthless, as he showed no remorse in executing exorcists as the head of Ritsu, even wanted to kill more innocent people.
He can be very petty, as he was jealous of his son Seigen being chosen by Byakko, rather than being proud of this achievement.