Sin-in-law
The relationship a boyfriend has to his live-in-girlfriend's parents.
Girlfriend: Mom, Andrew and I are moving in together
Mom: Oh, you're going to live together before marriage? Great, how I've always wanted a SIN-IN-LAW.
Girlfriend: But we love each other!
Mom: That's great, your love can help keep you warm right alongside the BURNING FIRES OF ETERNAL DAMNATION
Mom: Oh, you're going to live together before marriage? Great, how I've always wanted a SIN-IN-LAW.
Girlfriend: But we love each other!
Mom: That's great, your love can help keep you warm right alongside the BURNING FIRES OF ETERNAL DAMNATION
sin-law
The parent of a partner in a romantic and cohabitating but unmarried relationship.
Sadly, John's sin-laws dropped by the house for Jane's birthday.