Japanese with Manga

I'd have to trade side dishes with 〜なきゃなんねー

Grammar Explanation: Must do with 〜なければならない

Manga panel from 怪盗セイント・テール showing example of I'd have to trade side dishes with 〜なきゃなんねー.
怪盗セイント・テール » Volume 2 » Page 89

Rina asks Asuka Jr. if she can eat lunch with him.

アスカ Jr.:
「やだね」
“No way.”
「女(おんな)と食(く)うとおかずとっかえなきゃなんねーんだもん」
“If I eat with a girl, I'd have to swap side dishes.”
Literal: “If I eat with a girl, I have to exchange side dishes.”
リナ:
「そんなことしないわよ！」
“I wouldn't do that!”

Key Points

1〜なきゃなんねー = rough spoken “have to”
  • とっかえなきゃなんねー is a very casual contraction of とっかえなければならない.
  • Here it means “I’d have to swap”, not that he already swapped anything.
2取(と)っ替(か)える = “exchange”
  • おかずとっかえ is casual speech for おかずを取(と)っ替(か)える, “swap side dishes”.
  • The object marker を is omitted, which is common in fast casual dialogue.
3Casual setup: 女(おんな)と食(く)うと
  • 女(おんな)と食(く)うと means “if I eat with a girl”.
  • 食(く)う is a rough, boyish casual verb for “eat”.
4んだもん gives his excuse
  • The ending んだもん presents the previous statement as his reason for saying no.
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