An indoor amusement park based on eating - get gyoze/potstickers in mock Chinese alleys, ice cream in a huge shop/fair and buy cream cakes and eat them in the Tokyo creampuff field beneath trees with cream puffs on them. A baffling and bewildering experience inside Sunshine City.
Underground to Ikebukoro, then follow signs to Sunshine City
Updates
They are not "mock Chinese alleys", they are mock Japanese alleys. They look much like some of the alleys that are near the hotel and Namcoland...
Is this your business?