Tubame Syndrome
Rated 16+ Ongoing Released: 2004
Taiga has no memories from more than two years ago, after his parents die in an accident. He lives with his sister, Tsubame, until he discovers that she is from outer space and has been assigned to protect him. Taiga is the bearer of the Origin Heart, the reason Tsubame has this duty. Together, the siblings face the unusual circumstances surrounding his past and her mission.