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luxury; extravagance
treat (i.e. at someone's expense)
今日きょうは全部ぜんぶ私わたくしの奢りおごりだ。
Today it's all my treat.
奢りおごりでごちそうになった。
I was treated to a meal.
奢りおごりは気持ちきもちの問題もんだいだ。
Treating is a matter of feelings.