Eric Sweet is played by Paul Antony-Barber.

Mr. (Eric) Sweet is the headmaster of the school, and he is part of the teacher's ancient society. He speaks often in Egyptian, and is worried easily. He is strict, but will listen to students opinions and concerns, making him fit for his job. Mr. Sweet also knows Rufus as the "Betrayer". It is also hinted at that he has a crush on Mrs. Andrews. He is also very formal and can be excited sort of easily. Mr. Sweet, like Mara, is not always good at hiding things. He tried to avoid Mara's conversation about endangered hedgehogs while Patricia snuck into his office. All of the student's records are in his office, and he received an email from Mara about Mick and Mrs. Robinson because she was jealous of them. Mara usually goes to him with questions about her duties as school representative.