living in sin

listen to the pronunciation of living in sin
English - English
Present participle of live in sin
live in sin
To cohabit as if man and wife without being married

Builder: No. It's—it's that she's gone and—and not got married. . . . I suppose you'd have me eat humble pie and tell Athene she can go on living in sin and offending society.

live in sin
live together when unmarried (man and woman)