"Turtles." Tachibana Leo, 16-year-old, hates that word. Because it reminds him of his childhood when he had to play with Tsuwabuki Tenma, a crazy girl with a huge love for animals. Poor Leo had to go through a lot of things because of her. After studying overseas for 10 years, he comes back to Japan to take revenge on her, but 10 years is a long time and a lot of things have changed since then, including Tenma herself.