how dare you; how could I; what nerve
Rhetorical expression of indignation or disbelief that someone has the audacity to do something. Often used with a following clause stating the action. Rare and literary; the more common equivalent is どの面下げて.
See also: どの面下げて
How dare you come here again?
How could you have the nerve to say such a thing?
Alternate spelling using 顔 for かんばせ; less common and may be confused with other readings.
The expression is composed of 何の (what kind of) + かんばせ (face, countenance; an archaic word) + あって (having). Literally 'having what kind of face', it is a rhetorical question expressing that one has no right or shame to do something. The exact historical derivation is uncertain, but it follows a pattern of similar expressions using 面 (つら) or 顔 (かお).