Little sucker's obsession with the environment (8)

'the environment' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'little sucker's obsession' is the wordplay.
I cannot quite see how this works, but
'obsession' could be 'bug' and 'bug' is found within the answer.
The remaining letters 'green' is a valid word which might be clued in a way I don't understand.
This may be the basis of clue (or it may be nonsense).

'with' acts as a link.

Can you help me to learn more?