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Shinji (Japanese: シンジ Shinji) is a recurring character from the Pokémon Gotta Catch 'Em All manga. He is one of Shū's many rivals.
Shū met Shinji for the first time in Shinji: The Demon's Revenge, initially mistaking him for a Primeape. Shinji started off by yelling at Shū, who did not recognise him at all. When Shinji mentioned having seen Shū three days prior, he remembered that was the day he captured a Geodude. Shinji explained that Shū and Pikachu accidentally stepped on him and his Primeape while chasing after Geodude, injuring his nose. Shū apologised, but Shinji was still furious, commanding his Primeape to attack Shū and Pikachu. Shū tried to run away, but Primeape kept chasing after them, so Shū commanded Pikachu to fight back with ThunderShock. However, the attack barely affected Primeape. Shinji asserted that he can't battle unless he is angry. He explained that he used to be a happy Trainer, and showed Shū an old photo of him and Primeape, but that now he is miserable due to Shū's actions. He shouted and cried that he would never rest until he got his revenge on Shū. As Shū and Pikachu discussed that they felt guilt for what had happened, Shinji commanded his Primeape to attack Shū, hitting him in the face. As Shinji was dancing gleefully, he fell down from the rock he was standing on, knocking out one of his teeth. Shū grabbed the tooth and ran away with Pikachu as fast as he could.
Shinji reappeared in Shinji: The Return, demanding revenge over his missing tooth. Shū tried to shrug it off, inviting Shinji to eat lunch with him and Pikachu. Shinji yelled incredulously at Shū, asking if he would really expect him to accept his invitation. Nonetheless, Shinji accepts anyway, and shares Shū's food. Shū commented that Shinji must have been hungry, but Shinji insisted that the meal alone would not allow him to completely forgive Shū. As they boys were arguing, a wild Vulpix appeared. Shū prepared to battle and capture it, but Shinji stopped him, insisting that he should not use violence on a cute Pokémon like Vulpix. Shinji then reached out to pet the Vulpix, but it bit his hand. Shinji then decided to get revenge on the Vulpix, yelling and chasing after it. He chases Vulpix to a cliff, at which point it evolved into a Ninetales. Ninetales attacked Shinji with Fire Blast, burning him to a crisp. He commands his Primeape to fight back, and Shū commands his Pikachu to help out. When Ninetales was defeated, Shū told Shinji that he had changed his mind about him and could now accept him as a friend. Shinji refused to accept this, chasing after Shū and cursing him for interrupting his revenge.
Shinji is a rowdy boy who is easily angered and is quick to declare that he wants to take revenge. However, he cares deeply about Pokémon, showing a strong friendship with his Primeape and caring about small Pokémon like Vulpix.