Review of High School DxD
It's a highly etchi show (It's borderline from being hentai almost.) The main character just wants to lose his V card. He's surrounded by women who seem willing, but he's never able to pull it off. It's a show that teases, but never pays off. Keep in mind I only watched the first season, but I find it unlikely I will continue to watch this show. The characters don't really have any depth. The main girl takes off her clothes and sleeps next to the main guy to motivate him to do better at his job (sleep next to,no naughty stuff, everything is a tease as I said.)
I didn't talk about the general plot, which revolves around demons, or something like that, and the main character having some super secret power. Why? Because it's really just a device or reason for the show to exist outside showing you the women in awkward situations.
So, for a show that's about demons, it's lacking. And for a show about etchi, it never pays off. Does it really have much else to offer? Not really.