Fozziwig
Fozziwig was Scrooge's mentor and former employer. He was generous and joyful. Ironically, Scrooge became bitter and cold, as he only cared about money and not people in his business.
Love
Scrooge had the opportunity for love with a woman named Belle in his youth. Ironically, he chose money over a relationship with her, and it became the turning point of his life into bitterness.
Christmas Day
Scrooge has arrived to the Cratchit home on Christmas Day, and Bob is surprised to see his boss at their home. He expects Scrooge to do something that is out of bitterness and cruelty, but ironically Scrooge tells Bob he's giving him a raise and paying off his mortgage. He's a completely changed man.
Heat Wave
Scrooge's employees want to put more coal on the fire so they can warm themselves during their work as it is incredibly cold. Scrooge won't allow it and, ironically, the employees clamor that there's a "heat wave" coming through as they don't want to lose their jobs for being able to get warm, a threat Scrooge has warned them with.
Cratchit
Scrooge had the best of mentors who helped him to learn the business and become a man who was able to have agency in his ability to make money. Ironically, Scrooge does not provide that same type of mentorship to his employees, whom he merely treats as cogs in the wheel of his money making machine.
