Double Cast

is a Japanese light novel series written by Kyoichiro Takahata, with illustrations by Yu Kinutani. The series began publication on February 10, 2000 by ASCII Media Works under their Dengeki Bunko publishing imprint.

Synopsis
Ryosuke Kawasaki fell from the roof of the building and lost consciousness. I woke up in a strange house and headed home, but what I saw there was my funeral. Ryosuke Urawa encounters a fall accident of a strange young man on his way home. Ryosuke faints in the face of a disaster. It was the beginning of mysterious amnesia. Aki Kawasaki was confused by a strange boy who behaved like his late brother. But she gets to know. The crisis that approaches you and the heart that tries to protect you ...