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> 「じきに夕食の支度もできると思いますよ。  
>  どうです、いっしょに？」
>
> 「ラッキー！  
>  それじゃ、ごちそうになってこうかな。」

My attempt - So, it's your treat then?
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2017-08-30T11:14:22.983
52842
2017-08-30T11:45:00.703
2017-08-30T11:45:00.703
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question
meaning
What is the meaning of ごちそうになってこうかな?
The nuance is more like "I guess I'll take you up on that offer."

ごちそうになる is the standard polite expression for eating a meal that was prepared
by someone else or at someone else's expense, and it includes an element of
gratitude for the favour (similar to ～ていただく forms). The form ～てこう is a
contraction of ～て行こう, ie. "I'll do X before I go", and the かな introduces a
slight uncertainty, as in a "maybe" or "I guess". So the full ごちそうになってこうかな
literally means something like "maybe I'll eat here (gratefully, at your
expense) before I leave".

"So, it's your treat then?" doesn't really work as a translation because
there's nothing in the response that's questioning the first speaker's intent.
The first speaker has already made a clear offer to provide a meal, and the
second speaker is simply accepting with an "Oh, nice! I guess I'll do that,
then."
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2017-08-30T11:42:10.053
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2017-08-30T11:44:28.653
2017-08-30T11:44:28.653
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answer