Because this is chance encounter with 〜ので


Grammar Explanation

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When Cocoa picks up another student’s dropped handkerchief, she uses the opportunity to show off her devilish nature to Chiya they discussed earlier.

ココア:
「これも(なに)かの(えん)なので今度(こんど)(ひる)一緒(いっしょ)にどうですか?」
“How about we have lunch together next time, since this, too, is a meeting of chance?”
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