This is a really sad yuri anime that was a hentai game at first. I really liked it exept it was all emo at the end. Basicly a girl, named Hatsuki, loves her older adopted sister, Hatsumi. But on the night of Hatsumi's 16th birthday, she disapears from the earth and Hatsuki teams up with a universal witch and her talking bird-like animal to find her. You can find the episodes on YouTube.