Disclaimer: I don't own High School DxD or it's related concepts and characters, but Ichiei Ishibumi and his affiliates do.
The Other Dragon of the Student Council
After being reincarnated into a Devil by Sona Sitri and joining her Peerage as well as the Student Council of Kuoh Academy, Issei Hyoudou had worked himself into being both stronger with the Boosted Gear he possessed as well as stronger in character. While he could never stop himself from admiring the female body, he did work on his reputation of being one of the most perverted students on campus and helped with the real work that comes with being on the Student Council. In the Underworld, Sona's older sister, Serafall Leviathan, had actually took note of Issei's potential and invited him to star in her TV show which he did quite well in. Either way, he was aided in his efforts by his fellow Devils in Sona's Peerage, Genshirou Saji, who also possessed a Dragon-derived Sacred Gear, and Tsubasa Yura, who he had come close to since his reincarnation.
In the Student Council's meeting room, Issei and Tsubasa were stacking files before the latter, feeling both bored and bold at the same time, reached her right arm to pinch Issei right on his butt.
"Ah!" The Red Dragon Emperor yelped in surprise and turned to Tsubasa with an incredibly lack of comfort. "What was that for, Tsubasa?!"
The blue-haired student merely chuckled. "Don't pretend you weren't "awakened" in a manner of speaking."
As Issei sputtered in a failed attempt to respond, Tsubasa was quick to plant her lips on his.
As much as I like Sona, I'm pretty convinced that in a broad speaking sort of way, she probably wouldn't be so easily attracted to Issei as we know him in canon, and I didn't feel like leaving Genshirou hanging if he has any luck, you know. Luckily, Tsubasa seems to like Issei well enough amongst the Yuuto/Gasper/intellectual fangirls, so it felt natural. I'll do Serafall in a different one-shot, as well as Katerea and Coriana in their own. So be ready.
Anyway, while I do have some thoughts for long length stories based on High School DxD, I'm putting such thoughts in reserve for the future as I do some more work with other fandoms in the meantime. I kind of considered writing lemony pieces between him, Yasaka, Elsha, and Momo Momozomo, but I unfortunately don't quite know how to bring those ideas to life, no matter how inspired I was by the anime because of little things, like how Issei would meet Momozomo by chance, would he and Elsha "do it" in an AU of their canonical meeting, and when during the Kyoto trip would Yasaka be able to "reward" him among other stuff like that. Still, to any other High School DxD fans out there, don't be afraid to go beyond the boundaries while still respecting what's practical. In other words, I believe Rias doesn't need to be helplessly bashed, but that doesn't mean she needs to be in every fan-fictional form of Issei's love life, so Long Live Variety.
Enjoy the writings.