The location is great, situated in a nice neighbourhood close to a subway/train station that gets you everywhere easily. If you’re a walker, it’s not far on foot to a big park and several great areas.
The space itself is cute, modern and minimalist, although small (perhaps to be expected in Tokyo).
Our 11 year old, especially, liked sleeping in the upper loft. I should note that the beds are on the floor. The futon my husband and I slept on was thick, but still a little uncomfortable for my husband.