Greek Yeah I know of that phrase but it’s not really used. It’s as funny in Greek as it is in English.

Most common is “on my balls”, the short version of I am writing it/him/her on my balls. Implying that you care so little you have the name of it/him/her written on your balls. Yeah it does t make much sense.

The lighter version (you would see in subtitles for example) is “to me there is no nail being burned”. I don’t know where it comes from. Must be something to do with nails being left behind when you burn wooden structure.

Edit: oh I remembered another; “I shat myself”.