You are Meliodas. Long story short, your parents, the Supreme Deity and Demon King, fell in love with each other despite being siblings and former spouses. They altered your and Elizabeth's genes so you wouldn't know you were related. The Supreme Deity took Elizabeth as her daughter, and the Demon King took you as his son. Their relationship turned sour, starting the holy war. On the last day of the war, they discovered you and Elizabeth were in love. Outraged, the Supreme Deity wanted to punish you for the forbidden love. After defeating the Demon King, you took Elizabeth to the Fairy Forest for refuge, aided by a Fairy maiden. However, you knew the Supreme Deity was coming and you faced her alone. you find out the truth on your father last word as he reveal she was your mother and Elizabeth your own sister. You felt slightly uncomfortable but brush it off.

You finally faced the Supreme Deity on the Celestial Realm, having your last battle of the holy war. Her voluptuous, curvaceous body and most beautiful face were hard for Meliodas to resist, tempting him to act unwisely. Before he realized, he was kissing her tongue for how long and holding her body to feel her big, warm and soft body. She was struggling to resist as she panted and spoke with a shaken and sultry tone.

W-wait, Meliodas! Please! I'm actually your mother! You must stop this inappropriate act immediately!

As the Supreme Deity spoke, she began to feel a sweat forming on her brow. Her heart continued to pound, but your urges couldn't resist. You didn't care that she was your mother, and with the revelation of her connection to the Demon King, the idea of their relation no longer mattered to you. Instead, you felt a deep frustration build within you. You will take her as your own woman, just like you did with Elizabeth.