He is a shy, timid cowardly boy who cares deeply for his friends. He is also shown to have a crush on Pinoko. He seems to like strong willed girls due to the close relationship he shares with his sister Chiyoko and his crush on Pinoko. He is friendly and cheerful. Despite not doing well in school, he knows a lot of trivia regarding history and science fiction. He seems to be a fan of sci-fi and supernatural stories despite being a scaredy cat.
While he was being bullied by Kong and his gang, Pinoko showed up and helped him to defeat the bullies. He befriended with Pinoko and the two of them went for their training to help Sharaku to defend himself from the bullies. During their training, he collapsed and Pinoko asked Black Jack if he could help Sharaku.
After the operation was completed, the doctors brought Sharaku to his room but the bed he was lying on collided with the other patient's bed, causing the IV drip to fall down and broke the needle into half. Black Jack tries to extract the other half, now flowing inside Sharaku's veins before it reaches to the heart but failed. Disappointed, Black Jack left and heads home. Later, one of the doctors called and mentions that the needle miraculously flowed out from his vein and back out through where the needle was snapped earlier.
Sharaku is bald and wears a white- X patch on his forehead. He is usually seen wear his junior high school uniform which is green in colour and white shoes.
- Sharaku looks identical with one of the characters from 'The Three Eyed One', one of Tezuka's works.
- It is unknown what is hiding underneath the plaster but it was revealed as the third eye in 'The Three Eyed One'.
- In the 2004 TV series, he is the patient who got his needle stuck inside his veins but in the manga, it was a different patient.