一個願打，一個願捱 (jat1 go3 jyun6 daa2, jat1 go3 jyun6 ngaai4) — both parties are willing; one likes to hit whilst the other is willing to suffer [written and colloquial] in Cantonese
jatˉ¹一go˗₃個jyunˍ₆願daa2,打，jatˉ¹一go˗₃個jyunˍ₆願ngaaiˎ₄捱简 一个愿打，一个愿捱
Mandarin Pinyin: yi1 ge5 yuan4 da3, yi1 ge5 yuan4 ai2
Meaning of 一個願打，一個願捱
nounboth parties are willing; one likes to hit whilst the other is willing to suffer [written and colloquial]
idiomOne willing to strike, the other willing to be beaten; mutually consenting.