Stage forms this act uses in the library, and how often.
One friend has been explaining how special a certain ball is.
Seriously?
Textbook本当ですか？Slang 'マジ' ('serious') plus 'で' replaces '本当ですか': 'マジで？' = 'For real?'
One performer describes the people of a certain prefecture, and the partner notices they keep making sharp comebacks.
Culture note Sharp comebacks (tsukkomi) are strongly linked with Osaka, and なんでやねん is the most typical Osaka-dialect comeback.
Why would I be?!
Textbookどうしてそうなるんですか。"なんで" is casual "どうして"; Kansai "や" stands in for "だ/な" and "ねん" for "んだ": "なんでなんだ" → "なんでやねん".
Two people are chatting about something you can get at around sixteen, right out of junior high.
Culture note The J.League is Japan's professional soccer league.
Same as the J.League, see?
TextbookJリーグと同じですよね。Tokyo-style 「じゃん」 ('isn't it?') becomes Kansai 「やん」, since Kansai uses や where standard has だ/じゃ. Compare 「一緒じゃん」 in line 3.
One performer describes a horror story set in the other's house and predicts the other's objections about it.
I brought my favorite picnic blanket.
Textbook私はお気に入りのレジャーシートを持っていきました。"持っていった" (past of "持っていく", "take along") drops the い and becomes "持ってった".