Another plot could involve Sora getting involved in the Rating Games. Maybe he forms his own team with some unlikely allies. He could introduce new strategies and fighting styles that change the dynamics of the games. This would also put him in direct competition with some of the more powerful characters in the series.
One idea could be Sora being a new exchange student at the school in the Highschool DxD universe. He could bring with him unique powers or knowledge that intrigue the main characters. For example, he might have a special type of magic that is different from what is commonly known in their world.
A more complex plot could be Sora having a hidden past that is somehow connected to the Devils' history in Highschool DxD. As he tries to uncover his own past, he discovers secrets that could either save or destroy the current order in the Devil society. This would make him a key figure in a much larger conflict within the fanfiction.
Look to Chapter 47 for the clearest answer. It begins with Qi is actually second???] [Did the production team make a mistake?, keeps building through Isn't Qi supposed to be first?] [So who's first?, and lands on Qi is so excellent and only got 17, yet Jiang Li comes in with 22?.
Chapter 770, "You're Actually Speaking Up for Her?!", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event.
The best chapter pointer here is Chapter 22, "Number 7203". It opens with Hearing this, Su Yinwan looked at Shang Shaojing with a face full of... and closes on Jiang Li's righteousness temporarily shut Jiang Yan up, but after a few....
Look to Chapter 40 for the clearest answer. It begins with [Jiang Li claims she copied this herself?, keeps building through But her calligraphy is actually this pretty?] [Jiang Li dares to boast,..., and lands on The handsome guys on this show are so difficult to deal with..
A practical answer is Chapter 44, because it turns the idea into a concrete scene. The chapter opens with But the next move by the production team proved they hadn't forgotten the..., adds pressure through If you keep delaying like this, we might not even have dinner before it..., and ends on Does.
Chapter 29 is the strongest chapter-level answer because it starts from Big brother, it's me..." The shadow suddenly spoke and it was Jiang... and follows through on Big brother, are you unwilling?" His mournful expression seemed to signal....
Chapter 32 is the strongest chapter-level answer because it starts from You should know, an ID photo is like a mirror for demons. and follows through on With airflow comes water flow, and your fortune will naturally improve."....
Look to Chapter 28 for the clearest answer. It begins with The next evening, Jiang Yan drove home seething with rage., keeps building through Before he even entered the dining room, he shouted angrily, "Lili, you did..., and lands on Lili then kicked his knee hard..
Chapter 808, "Dare to Spank Him?!", is the clearest early answer because it turns Jiang Buchen's situation into a concrete plot event. The chapter turns that into something concrete by moving from I don't listen, I don't listen," Jiang Bufan once again started his...
If you want the clearest chapter reference, go to Chapter 8. Early on, The resentment that had barely calmed among the crowd surged back two...; later, the chapter leans on Some of them were relatives of the Jiang Family, who felt it improper to....