feed off

US /fiːd ɔːf/
UK /fiːd ɔːf/
"feed off" picture
1.

to eat something as food

:
The birds feed off the berries in the garden.
Many insects feed off decaying organic matter.
2.

to grow stronger or be encouraged by something

:
The comedian seemed to feed off the audience's energy.
Some people feed off drama and conflict.