Well, regular Hulk fanfiction usually focuses on aspects like his superpowers, his relationships with other characters in the Marvel universe, and his heroic or anti - heroic deeds. However, 'hulk lemon fanfiction' (assuming 'lemon' is used in an inappropriate sense) would deviate from these positive and plot - driven elements and likely involve improper or adult - themed content which is not suitable for general discussion.
The main difference is the focus on the Red Hulk. Instead of the traditional green Hulk, this graphic novel is all about his red counterpart. His motives and actions are different from the green Hulk.
He could use his position of authority. Snape might confront the abuser directly. Since he's a teacher, he has the power to intimidate and put a stop to any immediate harm. He could also give Hermione a safe place to stay, like his own quarters (if it's within the rules of the fanfiction world).
Sure, She-Hulk is related to Hulk. Jennifer Walters, aka She-Hulk, got her powers because of a blood transfusion from her cousin Bruce Banner, who is Hulk. This connection is a key part of their storylines in the comics.
Captain America would be a great addition. His leadership and moral compass could guide Hulk and She - Hulk when they face difficult decisions. And his combat skills could come in handy during battles.