Tasogare ni Kirameku Shirogane no Kugan

A mysterious girl suddenly appeared before me and said, "You wanna change yourself?" It all destroyed my gray life.... "You wanna live as you like, get an extraordinary power, and get out of your boring life...?" Crimson to purple, purple to darkness. Something inside me changed in a gradation of colors. My monotonous life suddenly turned into a world full of vivid colors. Yes, it's time to get out of choking life. I've got thirteen days to use my power. "Right. Just enjoy it... for thirteen days." People who look down on me. People who stick around me. People who despise me.... It's my turn. I'll get even with you.... I'll get back everything for the next thirteen days. I won't need my fourteenth day if I can get satisfied...