Friendship is also a big theme. Sirius might rekindle old friendships or form new ones with other professors or students. It could be about how his loyalty to his friends is translated into his teaching and relationships at Hogwarts. He might also have to deal with betrayals, similar to what he faced in his own life, but this time in the context of the school environment.
One common theme is redemption. Since Sirius had a troubled past, many fanfictions focus on him trying to make up for his past mistakes as a professor. Another theme is family. He might be a father figure to some students, especially those who lack proper family support at Hogwarts.
The theme of mystery often pops up. Given Sirius' past with the Marauders and his time in Azkaban, there could be fanfictions where he is involved in solving mysteries at Hogwarts. Maybe there are hidden secrets in the castle that only he can uncover because of his unique knowledge and experiences. These mysteries could be related to dark magic, lost artifacts, or even the true identity of certain characters.
A practical answer is Chapter 134, because it turns the idea into a concrete scene. The chapter opens with After a brief noon rest, the production team was up to their antics again., adds pressure through Thus, Jiang Li's live stream was once again flooded with netizens coming..., and ends on [Are.
Chapter 99 is the strongest chapter-level answer because it starts from Seeing the man approach, one of the individuals with a long scar across... and follows through on Just as she was considering whether to practice a set of boxing, her phone....
Look to Chapter 144 for the clearest answer. It begins with Ordinary people would have been at a loss in this situation by now., keeps building through But Jiang Yan was, after all, Jiang Yan., and lands on He then noticed the hand—fair and slender, not at all like an auntie's..
If you want the clearest chapter reference, go to Chapter 112. Early on, These five people are supposed to be at odds.; later, the chapter leans on When did they become so in sync?] [I'm dying of laughter hahaha why is....
A practical answer is Chapter 167, because it turns the idea into a concrete scene. The chapter opens with By the experimental field, Qi Tianyu was quite helpless as he watched Wen..., adds pressure through I'm not familiar with the others;
If you want the clearest chapter reference, go to Chapter 117. Early on, Fragrant and cloyingly sweet potatoes and corn were out of the pot, and Qi...; later, the chapter leans on The searing heat made him grimace in pain, but he didn't let go, and he....
Look to Chapter 115 for the clearest answer. It begins with Jiang Yan was woken by a loud crowing noise., keeps building through Annoyed, he opened his eyes and saw that the hen, which should have been..., and lands on [Pure bystander, wasn't Jiang Yan known as a notorious playboy?.
The best chapter pointer here is Chapter 165, "Boom! Jiang Yan is actually Su Yinwan's fanboy?!". It opens with How come everyone else got a solid six points, and he ended up with just... and closes on Various explosive Weibos sprang up like mushrooms after the rain, and....
Look to Chapter 130 for the clearest answer. It begins with This task, the first one, should have been his in the bag., keeps building through However, just as he was about to get out of the water and take a short..., and lands on Normally, the best planting distance for sweet potato seedlings is.
The best chapter pointer here is Chapter 151, "He Yun is quite good, but we are not fated to be together". It opens with Now it was Zhang Cheng's turn to be confused. and closes on I will have my assistant pay the bill.. The reason it matters is that the chapter closes with Was he...