Overindulge bear, say (6)
I believe the answer is:
Here is my best explanation:
'overindulge' is the definition.
'bear say' is the subsidiary indication.
'bear' becomes 'panda'.
'say' shows a homophone (sound like).
'panda' is a homophone of 'pander'.
(Other definitions for pander that I've seen before include "Give gratification (to)", "Gratify weakness like a pimp", "Cater for vice or low tastes", "Bow (to)", "Indulge base desires", "Satisfier of someone's baser wishes", "Cater for debased taste", "Cater rto debased tastes", "Gratify weakness or base tastes" and "Cater to lowest tastes".)