The Professor is a Pig Trader Mob exclusive to the Hamlet DLC. He is an elderly pig that buys relics for a Tenpiece Oinc, with no limit to the amount of trades in a day. He can be found at the Academy (signified by a triangle in a circle on the Map) in the Pig Village.
One Professor may spawn from a Town House, and will wander randomly around their house and eat any edible items left on the ground, including Pig Skin. Every so often they will drop one Manure where they are standing, and if the player picks up that manure the Professor will approach them and give them one Oinc, along with an accompanying Quote.
Whenever there is a hostile mob nearby, or a player targets them or another Pig Trader or Royal Guard near them, they will enter a panicked state. They will begin to move around semi-randomly in a direction away from the aggressor.
They will attempt to return to their house in the evening, and if they cannot reach their house or their house is destroyed they will seek the nearest light source and stand next to it until night, when they will sleep on the ground.