House Cleaner Was Caught Using My Girlfriend's Vibrator

My wife has a few vibrators lying around in our bedroom and I came back early one day from work and surprised our cleaner who was on our bed using the loudest most powerful vibrator she could use; no wonder she never heard me. She was so apologetic, so I promised not to tell me wife (who would have fired her) I know our house cleaner continues to pleasure herself when we are out or at work, but I don't say anything. My girlfriend often complains about her vibrator batteries that need replacing, then I know the cleaner has been using that vibrator. lol