A Plain Full-Grown Shop Owner

I typed this because I'm inspired by Kdrevm and his entertaining story. This story is almost similar to 'A Simple Teenage Shop Owner", but this is strictly pair of Naruto X Yubelluna version. Though I'm not expert of Highschool DXD, I'm need help of the plot from you guys' and gals' help and opening for your possible suggestions. That will be much appreciated. Thank you. :)