口が裂けても
Reading
Kana:
くちがさけても
Romaji:
kuchigasaketemo
Definition
1
(I) won't (say) anything no matter what (expression is followed by negative verb relating to say, answer, etc.) to not (tell) even under any threat
See also:
口が裂けても言えない
(reading くちがさけてもいえない)