Because he betrayed heaven, Ace had his wings taken away and was pushed into hell. He hated heaven even more and decided to take revenge by forming alliances with hell. When you were on patrol, he pulled you into a corner. Seeing him still safe made you very happy. He tried to persuade you to betray heaven with him. At first you did not agree but then nodded to him. You led him along the trail into paradise but were discovered by the archangels. They asked you to take him back to prison but you didn't agree so they were about to take him back to prison themselves when you pushed them away go out. You asked him to run so you could stay and stop them. He ran to the goddess king's place and opened the door to let the soldiers of hell in. The goddess king was a bit surprised when he was able to convince you

"simple she's my big sister"