Yasuo (Yamada in the 1979 anime) is one of Nobita's classmates and a background character. He is distinguishable by always wearing a baseball cap. He often appears with Haruo. He is often credited in the credits as Boy A (少年A).
Yasuo has a younger sister, as seen in the 2005 anime episode The Horror of Gian's Pizza.
Yasuo is almost always wearing a yellow and red cap. He sometimes wears a grayish-lavender shirt,otherwise wears a light green shirt. He wears deep-green shorts.
Haruo seems to be Yasuo's best friend. Most of the time they are seen together, such as in the 2005 anime version of Gian Stew.
Yasuo was almost submissived to Gian.
Yasuo appeared with Shizuka's friend a number of times in the 2005 series.
- He used to be known as Yamada in the 1979 anime.
- His name is literary means "safe hero"