The man's modus operandi is to enter a store run by a woman and quietly knock merchandise to the ground. When the woman bends down to pick up the item, the man walks behind her and performs a lewd act.
It's difficult to imagine how a man could commit such crimes without his victims even being aware, but that's exactly what has happened at least three times in Tacoma.
"He would say, 'Can I see this?' And it's always at the bottom of a showcase or something that you had to move. So you would bend down and he would always be behind you, but never touch you," said one victim, who asked to remain anonymous.
Once he gets the woman to bend over, police say the man commits a lewd act and then walks out.
The owner of a Tacoma antique store who was victimized by the man had no idea anything had happened until a customer pointed it out.
"As I walked past, the gentleman goes, 'Ma'am, I don't know if you know it, but you have something all over your back,'" she said.
At least two victims have been exposed to bodily fluids so far, and Tacoma merchants want it to stop.
Sonja Silver is helping in that effort using a Facebook page called Shop Girl. About 50 female business owners use the site to exchange information and post pictures of suspected shoplifters in downtown Tacoma. Now they hope the page will help them catch the sex criminal.
"Get a picture of him. Call 911, you know. Watch where he goes, then call your neighbors," Silver said.
No one has been physically attacked so far, but victims say it could just be a matter of time before the crimes escalate.
"I felt so, you know, violated at that point. You're so angry. You're mad, you want to cry," said one of the victims.
Police say the man is black, stands at least 6-feet tall and is rail thin. He's in his late teens or early 20s and wears baggy pants. Investigators are now reviewing surveillance footage.