Kintarou's motto is described something akin to "if you get me, i'll get you back". He learned that motto from Sugi who "taught" him tennis. She didn't really teach him as Kintaro was boasting that he could win at any sport. She got annoyed, challenged him, and proceeded to defeat him. Kintaro said that tennis was boring and she taunted him. He then tried daily to get back at her.