It would be hard to find nicer and more accommodating hosts than Kotaro and Kei. They have a real passion for meeting, talking, and entertaining complete strangers– something that you might find a rarity among the usual busy couples of Japan (I know, I live here!). They've warmth and a friendliness that is unmatched, and I definitely plan on coming again, as I sought a place to stay, but made two good friends as well.
The room is better and more comfortable than a lot of what you would get for the same or higher price in Japan, and Kei even cooks you breakfast.
There's no reason why you shouldn't say here if you're traveling around Tokyo. Not only are they conveniently located close to Shinjuku, but you'll make two great friends, taste Kei's amazing cooking (maybe she'll teach you to make gyoza!), and laugh at Kotaro being goofy; it'll brighten your whole visit to Japan, I promise.
They make me want to venture to Tokyo every month.