Preston Northwest

Preston Northwest is the Patriarch of the Northwest Family, a very rich man he is the decedent of the towns supposed founder Nathanial Northwest (who Dipper and Mabel proved to really be an idiot who got given the role as part of a Government conspiracy to hide the true founder) and the father of Pacifica Northwest.

While appearing just a selfish rich man, Preston proved to be one of the most callous and unpleasant people that Dipper ever faced, worse than many of the actual supernatural threats he had to battle.

History
Preston is introduced in "Irrational Treasure" celebrating Pioneer day with his family and using his relation to the Town's supposed founder as an excuse to lord his superiority over the people.

He later returns in "The Golf War" to drop his daughter off at a match between her and Mabel, however rather than stay to support his daughter, he and his wife leave to go to a party and gives her these words of advice "Don't loose"

But its not until "Northwest Mansion Mystery" that Preston shows just how evil a man he truly is, in fact he was the true main antagonist of the episode. Following his ancestor Nathanial cheating many lumberjacks into building there mansion a hundred and fifty years earlier, by promising he would invite them all to the annual part they held then refusing to let them in when he time came to hold up his end of the bargain. One lumberjack who died swore a curse on the Northwest line, unless they agreed to honor the promise and let the common folk go to there party after 150 years he would return to get his revenge.

As the curse began to come true, rather than opening the gates and letting the common folk in, Preston instead forced his daughter to manipulate Dipper into getting rid of the ghost. Its revealed in this episode as opposed to simply being neglectful, Preston is outright emotionally abusive towards Pacifica to the point of training her to respond to a bell like a dog.

After Dipper succeeded in trapping the ghost, Preston thanked him and then began welcoming the guests, however upon Dipper finding out the truth he angrily stormed back in and called Preston out for his callousness and deception. Preston forced his daughter not to apologies before callously dismissing Dipper and his anger.

After the ghost got free and began terrorizing the party, rather than agree to break the curse and save his guests, Preston instead hid with his wife and a butler in the panic room leaving everyone else to there doom.

Now the ghost had turned everyone into wood and planned to burn the mansion down killing everyone, Pacifica decided to go against her families legacy and break the curse. But Preston ordered her not to, and ordered her to join them in the panic room (revealing he planned to kill and eat the butler if the food ran out before ghost left). However finally standing up to her abusive father Pacifica opened the gates, letting the common people in and breaking the curse. This undid the ghosts damage and saved everyone. But Preston's only response was shock at the common folk being in his party.