Kanijo thought that his life was pretty dull until a strange boy with a thunderbolt 'tattoo' showed up at his door one day, passed out. Now, Kanijo's life is changed forever. Ever since the strange boy has entered his life, there's really never a dull moment for Kanijo. His life is now filled with laughter, company and perhaps, some romance. But that's not all. Kanijo later finds out that some strange people are after his new friend and he's not sure why but he bets all his money that it revolves around his friend's strange 'tattoo'.