I got a letter just the other day. She sent a picture but she didn't sign her name. She wore high heels and a little black lace. I knew her body but I couldn't see her face. She didn't leave a number not an address or a clue. But something in that photograph reminded me of you. Baby let's put the X in sex. Love's like a muscle and you make me wanna flex. Baby let's put the X in sex. Keep it undercover baby let me be your private eye. I got a call in the middle of the night. Heavy breathin' never sounded quite so nice. She said "Oh yeah I wish that I was there". I asked who was calling but she wasn't playing fair. Sometimes you gotta suffer for the pleasure that you seek. You're beggin' for an eyeful but you only get a peek. Baby let's put the X in sex. Love's like a muscle and you make me wanna flex. Baby let's put the X in sex. Keep it undercover baby let me be your private eye. I heard somebody knockin' so I opened up the door. She wore a hat shades and a trench coat. Wasn't wearin' that much more. She said she knew my secrets but I didn't have a clue. Then I saw those black lace panties and I knew that it was you. Baby let's put the X in sex. Love's like a muscle and you make me wanna flex. Baby let's put the X in sex. Keep it undercover baby let me be your private eye. Let's put the X in sex. Love's like a muscle and you make me wanna flex. Baby let's put the X in sex. Keep it undercover baby let me be your private eye. Let's put the X in sex. Love's like a muscle and you make me wanna flex. Baby let's put the X in sex. Keep it undercover baby let me be your private eye. Let's put the X in sex. Love's like a muscle and you make me wanna flex. Baby let's put the X in sex.