Eric is a proud, confident young man. Swallowing that pride and submitting to this spanking was not an easy decision for him. He's also nobody's fool, so he understood right away (unlike many of the boys) that the spanking was meant to be embarrassing and demeaning. That said, having agreed to it, he takes his spanking like a man.
Tom uses his hand, a leather slapper, a birch and two belts on Eric. Eric made the mistake of wearing a leather belt to his spanking, so Tom used Eric's own belt on him. (that's something he'll likely remember every time he wears that belt).