The main themes can vary widely. But often there is the theme of adaptation. Since she is in the High School DxD world, she has to adapt to different situations. Love is also a theme sometimes, whether it's romantic love or love for her comrades. And there's the theme of destiny, like what her true purpose is in this fictional universe which is full of magic, power struggles and various factions.
If you want the clearest chapter reference, go to Chapter 189. Early on, Seeing his painstakingly planted roses trashed like this, even as a fan of...; later, the chapter leans on Wenwen, I beg you, please take good care of my land!" "LOL, since when did....
The best chapter pointer here is Chapter 186, "The Goddess Who Can't Stand the Smell of Pig Manure". It opens with Seeing Wen Jiaojiao bravely entering the pigsty, Jiang Yan couldn't stay... and closes on And in the instant she fell, the red rope tied to Jiang Yan also broke,....
A practical answer is Chapter 192, because it turns the idea into a concrete scene. The chapter opens with Jiang Shixu had never imagined that Jiang Cheng, who had been so arrogant..., adds pressure through Let this incident pass, don't dwell on it and hurt yourself., and ends on Jiang Li.
A practical answer is Chapter 225, because it turns the idea into a concrete scene. The chapter opens with When Zhao Lang's devastatingly handsome face appeared, all six people..., adds pressure through Alright, it's about time, let's officially get started., and ends on Which big shot is.
A practical answer is Chapter 165, because it turns the idea into a concrete scene. The chapter opens with How come everyone else got a solid six points, and he ended up with just..., adds pressure through And this scene was fully witnessed by Zhao Lang from the second floor., and ends on Various.
The best chapter pointer here is Chapter 190, "Aren't We Friends?". It opens with Several people who didn't understand fell silent. and closes on Because he saw the pack of cigarettes pinched between Jiang Li's fingers..
Chapter 207 is the strongest chapter-level answer because it starts from After finishing, Sister-in-law Lan quickly took out the Good Evaluation... and follows through on She had taken care of them for a longer time, she hadn't even had lunch,....
Look to Chapter 179 for the clearest answer. It begins with Everyone originally had no expectations for the gifts that Su Yinwan..., keeps building through Although they felt there might be a catch, a few people still curiously..., and lands on I've been craving one for a long time!" Fans: ?.
A practical answer is Chapter 174, because it turns the idea into a concrete scene. The chapter opens with Does Young Master Jiang really care why I would come here?, adds pressure through My clothes were soaked, and I was too uncomfortable if I didn't change., and ends on She knows the camera is.
If you want the clearest chapter reference, go to Chapter 173. Early on, Jiang Li finally rose from her seat.; later, the chapter leans on Seeing her stand up, He Yun also stood up..