Evan was a rich man. His had a lavish apartment. Lupin had been to his place once or twice with other staff members. Evan had got a lot of money, lot of connections, that was why he was the bad boy of the area - the alpha of the vicinity.
Everything about Evan was despicable yet women and girls alike liked him. His confidence was fake and it was because of his money and power - parental money and the power generated from that money. Lupin thought: Give me that much of money I would be a better alpha. Alphas are bullies. He had a Rolls Royce Phantom. People used to worship his Instagram photos with that car or his exotic vacation photos. He was a god. He was a Batman or an Ironman or a Malfoy. Then why on earth he joined the school as a teacher. Perhaps it was his cover.
Evan was always around him to save him or save his face. That was why he felt obligated to attend the party. Besides really he did not have anything else to do. He stopped his car before Evan's lavish mansion.