Well, Hagrid would be a great addition. He could bring in some friendly magical creatures for the preschoolers to see, like baby owls or small unicorns. The kids would be thrilled to meet them.
Hermione would likely be there. She's Harry's best friend and would not let him be in juvie alone. She'd probably be trying to find a way to get him out legally, researching all the laws and loopholes. Ron might also show up, being another one of Harry's closest friends. He could be the more impulsive one, thinking about breaking Harry out rather than going through the proper channels. Dumbledore might also be involved in some way. He has always been a guiding figure for Harry, so he could be working behind the scenes to ensure Harry's safety and find a way to clear his name.
Hermione would surely be a main character. She could be a fellow teacher, perhaps teaching Transfiguration or History of Magic. She would be the one Harry goes to for advice on teaching methods or when he has a difficult student. Another character could be Ron. He might visit Harry at Hogwarts and end up getting involved in some of the school's mysteries or helping Harry with a particularly difficult Quidditch - loving student.
Obviously, the illithid would be a main character. It could be a mysterious and powerful being that Harry encounters. Also, Hermione and Ron might still be important characters. They could be either suspicious of the illithid or try to help Harry understand it better. Dumbledore might also play a role, perhaps guiding Harry in his interactions with this strange new creature.
Maybe Harry Potter could teach the preschoolers magic tricks in a simple and safe way, like making feathers float. He could also tell them stories about Hogwarts and his adventures, inspiring their imagination.
Well, depending on what 'rq' stands for, it could be a group of original characters created for the fanfiction. Maybe there's a wise old wizard who takes Harry under his wing as part of this 'rq' upbringing.
Hermione would probably be involved. She's always by Harry's side, and she might be researching ways to help Harry tame the basilisk. Maybe she finds some useful spells or information in the library that gives Harry an edge.
Hermione would likely be a main character. She might be the one who tries to guide Harry in using his new powers wisely. Ron could also be there, perhaps being a bit in awe of Harry's new status but still being his loyal friend. Dumbledore might also play a role, even if it's from beyond the grave. His wisdom could be a guiding force for Harry as he navigates his god - like existence.
Obviously, Harry Potter himself is the main character. He is the one who is teaching himself potions.
The Weasley family in general would be involved. Ginny, for instance, would be heartbroken seeing Harry on Voldemort's side. The family's loyalty to Harry would be put to the test, and they would be among the main characters as they try to either bring Harry back or fight against him if he goes too far with Voldemort.
Hermione would definitely be involved. She's always been by Harry's side, and in this kind of fanfic, she would likely be helping Harry in his struggle, using her intelligence to figure out solutions to the problems he faces. Ron would also be there, providing his loyalty and courage in the fight. Dumbledore might make an appearance too, perhaps as a guiding spirit or in flashbacks, offering his wisdom to Harry as he battles towards salvation.