Take the east exit of Shinjuku station and you will see the shop Megane Super across the road in front of you. At the weekends, outside the shop, you can see one of the sales staff drawing a crowd as he raps about the products and services available inside. He's not decked out in any fashionable gear, just his regular sales staff clothes, which makes him look like a Japanese salary man on a karaoke night who just happens to have been beamed down outside the shop. He looks he's having fun though. Apparently he's attracted enough attention to have been featured on TV.
I didn't have my camera with me yesterday, but I did manage to dig up the following link at YouTube, where you can see him in action: