Albus Dumbledore

"Wizards and witches, teachers and students, welcome to Hogwarts...Nitwit! Blubber! Oddment! Tweak!" — Albus Dumbledore welcoming the students.

Professor Albus Dumbledore is the ancient headmaster of Hogwarts' School of Witchcraft and Wizardry. He is very old, wise and kind. His pet is a phoenix named Fawkes.

Stone
Professor Dumbledore is first seen at Privet Drive after celebrating a party of Lord Voldemort's defeat with lots of alcohol. At Privet Drive, he mistakes a stray cat for Professor McGonagall, which McGonagall finds amusing. Hagrid also appears in his flying motorbike and delievers baby Harry Potter to them. Dumbledore places baby Harry on the Dursleys' doorstep, locking Harry's eleven-year fate.

11 years later, Dumbledore appears at Hogwarts' as the headmaster and appears in the Great Hall. He is present for the Sorting and appears around Hogwarts'.

Chamber
Dumbledore also appears in Harry's second year, and is among the shocked staff who find people petrified around the school. However, he is arrested by Lucius Malfoy when people blame Dumbledore for not doing anything about all the petrifications. He is reinstated when the Basilisk is killed by Harry Potter.

Also, Dumbledore was the only one who didn't trust Tom Riddle.

Prisoner Da fuck?
After Dumbledore discovers that McGonagall stole his Firewhiskey supply, he gets angry at her and starts chugging rum instead. It is here we discover that he is a homosexual. He eventually confronts McGonagall drunkenly and rapes her, although neither of them remember a thing the next day.

Dumbledore also gives Hermione Granger a Time Turner, and after recalling Hermione's beauty, he decides not to be gay anymore and starts looking for single ladies.

Goblet
Dumbledore is delighted when Hogwarts' becomes the host of the Tri-Wizard, and is turned out when the ladies at Beauxbatons arrive, claiming he loves French women the best. When Madame Maxine walks into the Great Hall, they make out (making Hagrid jealous). When Harry is chosen for the Tri-Wizard Tournament, he is disappointed and is present in the crowd for all three tasks.

It is also revealed that Albus Dumbledore can read and understand ancient runes.