Husband and wife are about to have sex, the husband turns off the lights and they have sex, this keeps up for a long time, the wife asks ' why do you turn off the lights when we want to have sex '. The husband says ' cause it makes sex more fun '. Wife tries to believe what he said and they have sex. Wife plans to turn on the lights the next time they have sex. The next time they were about to have sex, wife turns on the lights and finds her husband holding an operating sex machine. Wife says ' you lying impotent bastard, you were using a sex machine on me ', husband says ' then how do you explain the kids '