Since their parents died at an early age, Susumu and Yoriko have lived together. Susumu is now 33-years-old and Yoriko is 40-years-old. Both of them have yet to marry. They are like most siblings and they rely on each other. One day, Susumu and Yoriko receive a letter that is sent to the wrong address.

Osamu Mukai
as Susumu Onodera

Hairi Katagiri
as Yoriko Onodera

Mizuki Yamamoto
as Kaoru Okano / Akira Asano

Mitsuhiro Oikawa
as Kosuke Kawada

Kumiko Aso
as Yoshimi

Nao Omori
as Keisuke Sakai

Minako Kotobuki
as Asako

Tsuyoshi Muro
as Kosuke Kawada

Masafumi Nishida
as