Something which is owed that is ruthlessly required to be paid back.
This derives from Shakespeare's Merchant of Venice, 1596. The insistence by Shylock of the payment of Antonio's flesh is the central plot device of the play:

The pound of flesh which I demand of him Is deerely bought, 'tis mine, and I will have it.

The figurative use of the phrase to refer to any lawful but nevertheless unreasonable recompense dates to the late 18th century.
by 345790 September 24, 2010
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persistent and/or unreasonable demands, largely made through misguided feelings of entitlement.
"It will be inevitable that the children will each want their pound of flesh during the holidays, so in order for us to make this vacation feasible, we will have to stand firm to our budget."
by TheMocker October 12, 2011
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Getting laid /sex from someone who you think owes your lame ass sex because you been doing favours for a while with the intention of getting some
Jerome been tryin to get a pound of dat flesh from Regina for a minute now. Been taking her to fancy dinners, paying her bills and even babysitting her kid but his boy Tyrone been gettin' a pound of that flesh every time while Jerome babysitting.
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