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Oswin Ham, or more commonly known as the Fat Friar, was born around 982 C.E. in the British Isles and attended Hogwarts School of Witchcraft and Wizardry in its second year as an institution. Sorted into Hufflepuff, he had a penchant for healing and thus he excelled predominantly in Charms, Herbology, and Potions. He was known to be jolly and very forgiving with a big appetite, and was one of Helga Hufflepuff’s favorite students.

After graduating from Hogwarts, the Fat Friar saw that there were many non-magical various poxes spreading among the Muggles. Feeling that he needed to help, he joined a mendicant religious order (a Christian order that has adapted a lifestyle of poverty to preach to the poor) as a clergyman, thus earning his title. The Friar personally visited the sick peasants out of the good will of his heart and cured their pox by poking them with a “stick” which, of course, was actually his wand. This made him be seen as a “savior” of some sorts to the poor, however the Muggles in his religious order grew more and more suspicious over time at his ability to cure the sick so easily.
As Ham continued to serve as a friar, he began to feel more and more comfortable with performing magic when there were witnesses, completely unaware of the clergymen’s suspicion. He began pulling rabbits out of the communion cup as a hobby. Even though it was hilarious to the friar, the clergymen in his order found the conjured rabbits to be blasphemous and disrespectful. One day, the friar was summoned to a meeting with the senior clergymen. Hopeful that he was finally being promoted to Cardinal due to his acts of kindness and healing, he cheerfully went into the meeting, only to be arrested for several accounts of witchcraft, making deals with the devil, and gluttony. He was executed at dawn the next day.

Upon his death, the friar returned to Hogwarts where he became the resident ghost of Hufflepuff house. Although his birth name was Oswin Ham, he hardly replies to that name anymore as he embraces the nickname given to him by countless generations of Hogwarts students. He retained his cheerful attitude that he had while he was alive, and remains one of the most loved ghosts in the school until this day. A portrait of the friar is hung in the first floor corridor. The friar himself can be frequently seen haunting the corridor and engaging in conversations with his own portrait.