Before practicing with swordfighting, Jaime Lannister asks Bronn if it's safe to practice, as he doesn't want anyone to know that he can't fight anymore. Bronn assures him by telling him that at this exact spot, he has sex with Leygood's wife and that she is quite the screamer. If no one can hear them, no one will hear Bronn and Jaime practicing.
In the books
In the A Song of Ice and Fire novels, there is no mention of the knight from House Leygood.