Nah, lets save it for later.

Maybe later, he still has Yuuma to deal with.

"I should just use this time to perfect my abilities and read the books that Sona gave me." Issei met with Sona again and ask her to bring him some books about magic and common knowledge of the supernatural. It would help him in the long run.

Who knows, maybe he could actually do magic, it's a stretch but the knowledge would help.

"Let see here theory of magic, Magic so easy a peasant could learn it, that sounds harsh-"

And so, the days go by as he prepares for tomorrow of the upcoming date.