Complete List of Characters (all those introduced so far)
Main Characters
Ciel Phantomhive - The protagonist of Kuroshitsuji
Albus Dumbledore - Come on, we all know who he is. Future Headmaster of Hogwarts, protagonist representative of Harry Potter
Other Students
Elphias Doge - In canon, Elphias is a close friend of Dumbledore.
Andromeda Ashford - Ravenclaw student
Matilda Prince - Slytherin prefect
Aries Malfoy - Slytherin Prefect
Marvolo Gaunt - Descendant of Salazar Slytherin, grandfather of Voldemort, Slytherin sixth year
Alexis Zabini - Slytherin first year
Professors
Phineas Nigellus Black - Current Headmaster of Hogwarts
Vivian Longbottom - Head of Hufflepuff house, Arithmancy professor
Kassidy Britton - Head of Slytherin house, Potions professor
Jameson Smith - Transfiguration professor
Professor Binns - History of Magic professor, currently alive
Corry Vanken - Defense Against the Dark Arts professor
Amy Sprout - School matron
Harold Potter - Flying instructor
Meyden Lockhart - Charms professor
Casey Forewindon - Divination professor
Shopkeepers
Tom (Last name unknown) - Owner of the Leaky Cauldron
Madam Kashmere - Owner of Madam Kashmere's Robes for All Occasions
Sawtooth - Gringotts goblin
Gerbold Ollivander - Owner of Ollivanders, grandfather of Harry Potter's Ollivander
Other Kuroshitsuji Characters
Sebastian Michaelis - Ciel's demonic butler, arguably the second protagonist of Kuroshitsuji
Finny - Ciel's gardener, who has inhuman strength
Mey-rin - Ciel's maid/sniper, who has inhuman eyesight
Bard - Ciel's cook, former soldier
Elizabeth Midford - Ciel's fiance
Madam Red/Angeline Durless - Ciel's aunt
Lau - An ally of Ciel's, opium dealer
Undertaker - An informant of Ciel's, mortician
Other Harry Potter Characters
Peeves - Hogwarts' resident poltergeist
The Bloody Baron - Ghost of Slytherin
Kendra Dumbledore - Albus' mother