slave to greed; slave to avarice
A person who is completely controlled by their own greed or material desires.
He thinks of nothing but making money; he is truly a slave to greed.
Compound of 欲 (greed, desire) + の (possessive particle) + 奴隷 (slave). The exact origin is uncertain, but it follows a common pattern of describing a person as a slave to a particular vice or obsession.