Ankokuji trained at the Gongenzaka Dojo back in the day, and he's always been a huge admirer of the former champion Strong Ishijima. But here's the thing—he and Yuuya have actual history. When they were kids, Ankokuji would constantly pick on Yuuya about his dad disappearing, bringing up how he basically ran away rather than face Strong Ishijima in a duel. Gongenzaka kept stepping in to protect Yuuya every time it happened. That whole situation left Ankokuji with a grudge against both of them, and it's something that clearly still sticks with him.
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