I'm pretty sure I've made Voldemort creepy enough.
The timeline here can be a bit confusing. The presumed-dead students – who were in Harry's year or one year above – were still at Hogwarts. But Fiendfyre is an advanced spell, so the most likely time for the attack is in (what would be) Harry's sixth year. So how is Granger an Auror already? When did Harry leave Hogwarts to become a notorious killer? Why didn't Voldemort return at the same time ze did in the books? These questions will be answered in time.
Approximate readability: 4.80 (400 characters, 92 words, 8 sentences, 4.35 characters per word, 11.50 words per sentence)