Suneo is the braggart who parades his material wealth in front of Nobita. He is often seen with Gian, who he bullies Nobita with. He actually hates Gian very much, so helping Gian to bully Nobita is probably to avoid suffering the same fate himself.

Several stories start with Suneo showing off some new video game, toy, or electronic device his family has bought, or him needing Doraemon’s help. He has an extensive knowledge of science, and he is a talented artist and designer. He also has a younger brother Sunetsugu (Sunetsugu?), who was adopted into his uncle’s family in New York.

In some scenes, Suneo is seen as a narcissist who loves to stare at himself in the mirror while telling himself that he is the most handsome guy in the world. He is still a bed-wetter and needs to wear diapers when he sleeps, despite being in the fourth grade. He considers this as his secret weakness, and according to his mother, it is his only weakness.

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