Shiro is a lead investigator following a serial killer known as ' The Red Lion'. Since he became head of his team he's been looking for the killer. With no witnesses or any details left behind Shiro had no idea who was behind it all, all he knew was that he was younger than him. Keith on the other hand knew about Shiro all his investigations and loved how persistent he was, he was convinced Shiro was in love with him just as much as he was.