Another version of the same Rosa Gigantea (Sei)'s past love story, titled, "Ibara no Mori." Maybe it's just me, but Shiori looks so cute in the book. Of course, everyone is cute in this series ;^)
On this story, too, I think anime had more impact. Along with excellect storyboard writing, great voice acting by Toyoguchi Megumi (Rosa Gigantea) really made the difference. Some of the more important moments in this story are Rosa Gigantea's reflective soliloquies, so it might not be fair to the manga.