Horus harbours deep feelings for Seth. Even if Seth has been deemed an evil God, Horus is aware that this happened only because Osiris tried to do unspokable things to Seth. Not being able to live with this feeling of constant filthiness, Seth chopped Osiris into 9 pieces and dumped him in the River of Duat. Yet Osiris - the God of Life, didn't die. He resurrected himself and came back to get Seth all for himself once again.