Cerberus is a three-headed dog in Greek mythology who guards the entrance to the underworld, which is where dead people go. He has three heads so he can see everything that goes on around him.
In the real world, Cerberus is also the name of a company that helps people, like banks and businesses, manage their money. They are kind of like a big piggy bank that keeps all the money safe and makes sure it gets where it needs to go. Just like how Cerberus in Greek mythology guards the entrance to the underworld, the Cerberus company makes sure the money is safe and doesn't get lost.