User blog comment:B214/Question and Answers 6/@comment-24098614-20170326152005/@comment-26821288-20170327094535

I think that, instead of magic, Issei should perhaps train his body till its very limits, and learn how to use Touki, just the way Sairaorg did. And it does fit his character. And I certainly do hope Ishibumi will do that. And I think it will strengthen Issei much more than learning magic or improving his Demonic Magic capabilities will, too.