1期OP http://jp.youtube.com/watch?v=At2FdwQd4rI&feature=related 2期OP http://jp.youtube.com/watch?v=WvClRy_JOJE&feature=related 3期OP http://jp.youtube.com/watch?v=RpZJjz8vrlI&feature=related 4期OP http://jp.youtube.com/watch?v=tkAkf0JAa-c…