Because strong players gather here with 〜ので


Grammar Explanation

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Cocoa inquires about the board and pieces sitting in front of Chino. Chino says it’s chess and gives a further explanation.

チノ:
「この温泉(おんせん)強者(きょうしゃ)(あつ)まるのでおじいちゃんは白熱(はくねつ)していました」
“Grandpa would get excited because strong players gather at this hot spring spa.”
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