Bother going topless - currency needed (6)
I believe the answer is:
rouble
'currency needed' is the definition.
I can't judge whether this definition defines the answer.
'bother going topless' is the wordplay.
'bother' becomes 'trouble' (synonyms).
'going topless' means to remove the first letter.
'trouble' with its initial letter removed is 'ROUBLE'.
Can you help me to learn more?
(Other definitions for rouble that I've seen before include "Currency of 13" , "9 Across currency" , "Unit of money in Russia" , "Russian money" , "ready in Belarus" .)