1x1 - Taboo Tattoo

One day Akatsuka Justice (nicknamed Seigi), a boy with a strong sense of justice, saves a man from some street punks. But the moment he touches the stone given as a token of the man's gratitude, a strange pattern shows up on the palm of his hand. The next day, when Seigi is baffled to notice that the pattern won't disappear, a mysterious girl appears before him and demands to know where he got the tattoo before suddenly attacking him.