Koenji is a small district, located just outside Shinjuku, near Nakano. Koenji is easily reachable by using the Chuo and Sobu line. It's a small and quiet neighborhood that recently gained popularity because its very vintage and eccentric shops scattered around.
Take the South Exit, and then proceede trough this covered shopping street and finally explore the so-called LOOK, a Japanese "shotengai" (again, it means shopping street).
My bad, I didn't really focus on the clothes shops, but I rather took a bunch of pictures of curious objects and views. I will go there again and take some pictures of people and the awesome vintage clothes they have there. As for now, enjoy~