what am I sticking my nose into?
De quoi je me mêle ?
What business is it of mine?
— Le Château ambulant (2004)
De quoi je me mêle !
What's it to me?
— La Haine (1995)
De quoi je me mêle.
Mind your own business.
— Delicatessen (1991)
Mais de quoi je me mêle ?
But what business is it of mine?