Cheap eating in Koto-ku

We�fre staying in Koto-ku across from Kiba Park and Museum of contemporary art. Where are affordable places to eat? Is there department store in Koto to buy raincoats (if downpour)?

There is Ito-Yokado in Fukagawa Gyazaria.
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I think there is a supermarket, raincoat also sells.
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In addition, there is a supermarket called Seiyu near the station of Toyocho.
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There is something to be eaten cheaper in Fukagawa Gyazaria.
In addition, there are a lot of dining options in a way going to Monzennakachou station from there.

Koto-ku (and other ku in Tokyo) are pretty large, so when you're talking about locations it's more helpful to mention which subway or train stations you're close to.

I'm guessing that you're near Kiyosumi-Shirakawa station. I don't know of any major department stores out that way, but you're just a few stops from Mitsukoshi Department Store in Nihonbashi.

There will be dozens of inexpensive restaurants surrounding the subway station; you should have no problem finding a place to eat near there.

Thanks for great tips, Haro and Umami. Re location, nearest subway to our apt is Kiba. Does that help you?

From Exit 4 of the Tozai Line Kiba Station, Fukagawa Gyazaria is about 3 minutes walk.
I went 3 times, there is also a restaurant and cafe, convenience store and movie theater in Fukagawa Gyazaria.
For more information, please look at the link of the previous comment.

It means you can go to the owl cafe! http://whereintokyo.com/venues/25411.html

Once again, you'll find dozens of restaurants within a few blocks of the station, and you're sure to find something affordable and good.

To Monzen Nakacho station from Kiba Station of Tozai Line is about a 10-minute walk.
On the way, there are a lot of shops that the locals visit often.
In addition, there is a Tomiokahachimangu and Fukagawa Fudoson, there are shops such as pickles and Japanese sweets shop, and a variety of shops.