Professor Severus Snape (9 January, 1960 – 2 May, 1998) was a half-blood wizard who was the son of the witch Eileen Snape (née Prince) and Muggle Tobias Snape. During his lifetime, Severus Snape was Potions Master (1981–1996), Defence Against the Dark Arts professor (1996-1997), and Headmaster (1997-1998) of Hogwarts School of Witchcraft and Wizardry (which he attended as a student from 1971 until 1978). He was also member of the Order of the Phoenix and played a very important role in both of the Wizarding Wars against Lord Voldemort.

Minerva McGonagall (October 4, 1935 - Caithness, Scotland) is a mixed witch and Animagus who attended the School of Witchcraft and Wizardry Hogwarts from 1947 to 1954 and was placed in Gryffindor. After graduating, she worked for two years at the Ministry of Magic and then returned to teach at Hogwarts, where she became the Director of Gryffindor, Deputy Director Transfiguration teacher, and after the Second Wizarding War, Director of Hogwarts.