Mr. Tsubaki

Hiroyuki Tsubaki
Gender	Male
Age	mid 60's (?)
Occupation	Retired (?)
Affiliation	Father of Youko and Akria / his wife is deceased

Mr. Tsubaki is Akira and Youko's father. He is first seen in Manga Chapter 12 / Anime Episode 13 when he and his children, the two siblings, visit their deceased mother's grave.