the.com/pound of flesh

means A harsh, literal repayment demanded from someone, with no mercy for the damage it does—getting exactly what the contract allows, even if it ruins them.

from Drawn directly from Shakespeare's The Merchant of Venice, where the moneylender Shylock demands, as collateral for an unpaid debt, a literal pound of flesh cut from the merchant Antonio's body. The phrase stuck as shorthand for any repayment that's technically fair but monstrously cruel—justice squeezed dry of compassion.