|Relatives||Unamed sister (deceased)|
|Anime Debut||Season 1 Episode 1: Boy Meets Girl|
|Seiyuu||Kousuke Toriumi (鳥海 浩輔)|
Yashamaru is a young man with wavy blue chin length hair swept to the left. He has gold eyes. He wears a single leaf-like earring on his right ear.
His main outfit consists of a beige striped jacket over a white shirt, skinny leather trousers and red boots with a white buckle. His alternative outfit includes a grey striped jacket (similar to his beige jacket) over a black shirt. He can also be seen wearing a proper suit on several occasions.
He loves B-Project and wants to help them grow. He is very playful but can get serious when he needs to be. He also has a sister complex as shown in the second season of the anime. In the past, he was very gentle and was very supportive towards his sister by using all his efforts to help her accomplish her dream as an idol. Even after ten years of her death his feelings didn't change at all.
|However, it is later revealed in the final episode of the first season that he holds a strong grudge against Tsubasa, as he claims that her father "killed" his family.|
- In the final episode of the first season, according to the editor-in-chief of the Kiss&Hug magazine, the name "Sakutaro Yashamaru"doesn't even exist, heavily implying that it is not his real name.
- In the first episode of the second season, it is confirmed that Yashamaru officially quit working at Gandara Music.
- He is now an employee at Highedge Records.
- He had a younger sister who was once an up-and-coming idol, but her career was hindered due to her frail health. However, he continued supporting her as her older brother.
- Yashamaru blamed Tsubasa's father for his sister's death, claiming he had betrayed her by giving a song he made for her to sing to another artist instead.