This private house was designed on a small, triangular plot of land by a river in Tokyo, Japan. The architects, Mizuishi Architect Atelier, utilised as much space as possible on the 29 metre squared space. The small house is crossed making an acute angle. For the dead-end road has various regulations which required special permission to b obtained for building.

The home was designed for a couple and their young daughter. Although it was a novel site with a limited area, with the river facing through a bank and a promenade, various relations to the river were used. The building is the form comes from a cut as an acute angle which is derived from the site. Furthermore, it has the maximum volume of hip roof on three planes. The level 1 floor is divided into small areas by structural narrow walls, being connected by the ridge-line of the roof. So there are different open feelings and relations with the river.