I am terribly sorry about your hammies death

But it may not have been a cruel thing. Owdie may have passed away form naturla causes or illness or something else and then from instinct Opel ate him. In the wild when a hamster dies the others eat it so that predetors are not attracted. Not all domestic hamsters do this but some do. It happens in gerbils, mice, even rats and some other small animals.

Again I am sorry to hear.