Consume Evian water around end of night, then pee (3,2)
I believe the answer is:
eat up
'consume' is the definition.
(I've seen this before)
'evian water around end of night then pee' is the wordplay.
'evian water' becomes 'eau' ('water' in French, eg to French company Evian).
'around' indicates putting letters inside.
'end of' indicates one should take the final letters.
'then' is a charade indicator (letters next to each other).
'pee' becomes 'p'.
The last letter of 'night' is 't'.
'eau' placed around 't' is 'eatu'.
'eatu'+'p'='EAT UP'
(Other definitions for eat up that I've seen before include "43 [TUCK] in" , "Consume, absorb" , "finish meal" , "Finish one's food" , "show good appetite" .)