As a young boy, Boingo is very introverted and timid. He prefers to act as support for his companions by showing the predictions of his Tohth rather than directly taking action. He is only comfortable around his brother, Oingo, sticking close to him and feeling lonely while away from him. His bond with his brother is deep enough that he promises to take revenge for Oingo's defeat all by himself, which causes Oingo to tear up.