Homemade Heroes

From MangaHelpers:

The children of the Sendai family--Retsuto, Akari, Marin and Mashiro--live in a very unusual home with their parents and grandfather. Below ground level, they have a command center, as well as R&D labs. The children are preparing to become heroes, in case a situation arises that can't be handled by the self-defense force or the police. Retsuto is enthusiastic about the idea, and Marin really loves ally-of-justice TV shows. Little Mashiro is skeptical about her ability to do anything as a 'hero.' This 4-koma shows their unusual daily life. [tethysdust]