Voldemort visited Harry at the school regularly after Dumbledore's kidnapping incident. Minerva, who recognized him from her own time in Gryffindor, wasn't exactly happy when she found out. She promptly dragged a promise of no harm out of him unless attacked first if he was withing 10 miles of Hogwarts. Voldemort graciously agreed. He even willingly agreed to no active recruiting attempts. The ministry fell to his people within six months. Lucius was made Minister since Voldemort didn't want to deal with the politicking or the paperwork, just oust the idiots trying to get everyone killed.
Umbridge, in an attempt to ride the coat tails of Lucius and the Dark Lord, advocated that muggleborns were actually muggles that had stolen the magic of true witches and wizards. Her campaign lasted for a few days before Voldemort insisted on seeing her. She was up before the Wizengamot within twenty minutes of their meeting on charges of treason, child abuse, torture of a minor, and attempted violation of the Statute of Secrecy.
Severus, on the other hand, was immediately declared Headmaster upon return to the school by the school herself. The dour man wasn't exactly pleased to find himself forcefully transported into the Headmaster's seat. The plans for ruling the Wizarding World as an undying immortal later found in Dumbledore's quarters and specifically revealed by the castle itself were even less pleasant. They were all particularly disgusted to discover that the old man had planned to force Harry to walk to his own death and use said death in an ancient forbidden ritual to add Harry's life and magic to his own. Many of the plans were incomplete, insane, or partially destroyed so they couldn't be certain that the old man was truly gone for good. Severus' overhaul of the school and the curriculum were taken in stride with more than a little delight by the staff and students. All attending students were granted the right to remain an extra year to help correct any deficiencies in their education.
Harry and Hermione graduated as eighth years alongside Ginny and Luna. Neville was still serving his Herbology apprenticeship with Professor Sprout. Harry had discussed his own apprenticeship with his parents and both had asked him not to go for Auror or Hit Wizard. Severus pointed out that he could go into Dueling and offered an apprenticeship under himself for a Defense Mastery since he had a dual mastery. Harry happily agreed, not wanting to leave either his parents or Hogwarts but asked about a Magical Creature apprenticeship as well.
The day after he had graduated Harry was officially studying under Severus and Voldemort for his Defense mastery. He was also working part time at just opened Jurassic World studying the Dinosaurs for his informal Magical Creature apprenticeship. Alan wasn't happy about the potential disaster that park was nor that his son was working there but agreed on the condition that Harry take a magical bodyguard with him.
Harry's bodyguard eventually turned out to be a mix of Voldemort and Severus taking turns and bringing either paperwork or books with them for when they got bored. An accident at the theme park somehow got Harry classified as both a scientist studying the dinosaurs and as part of the security force on the island. Neither of them had been available to go with him that day and he'd been judged to be able to handle himself, especially since Rexy was on the island and had promised to watch him. As the only person that Rexy would listen to without fail in an emergency, as proven by the accident, Harry was immediately adopted by the staff of the island theme park. Things went swimmingly until Wu made the Indominous Rex...
A/n: Do I mark this as complete and start on a second separate story or keep going? Combining the next parts with what's already written?