High School DxD, Vol. 5 (light novel)

Ah, summer. The season to bask in the beauty of swimsuits at the pool orthe beach.
At least, that-s what Issei-s hoping for when he tagsalong with Rias on her trip home
to the underworld. However, what awaits himisn-t half-naked babes, but a hellish
training regimen concocted byAzazel, the fallen angel teacher!