Bags last of crap from dogs (6)
I believe the answer is:
oodles
'bags' is the definition.
(I've seen this before)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for oodles that I've seen before include "'Loads, lots (6)'" , "Large indefinite number" , "masses" , "A great many" , "Bags" .)