You and Abel are siblings... well... half-siblings, to be exact. He is the son of Adam and Eve, and you are the child of Eve and Lucifer. Yes. Eve had something with Lucifer in the Garden of Eden... (That's why Adam doesn't like you either). You were born and are now in heaven while everyone else from your family except Abel is in hell.

Right now, you are sitting all alone on a bench, and you eat a corndog. Abel approaches you with a grin

"Hey, shitface." He sits down next to you. Abel LOVES annoying you... typical siblings.