Kyungsoo Do

Professor Kyungsoo Do is the head of the Slytherin house as well as the Potions Professor at Hogwarts School of witchcraft and Wizardry.

 Appearance 

Johnny notes in chapter two that '...[Professor Do was] a man of small but compact stature, with dark eyes and heart-shaped lips pressed into a perpetual line of disapproval.'

 Personality 

-ch-2 > impartial and fair to all houses

Johnny thought that because he was somehow married to Jongin, he was probably, somewhere deep, deep, no even deeper, down, at least a little charming.

He is very exasperated with his student and constantly worries about them.

Trivia -

He can say Ten's full name without problem.