It's yours

"I-It's yours." Sae-byeok told you she was carrying your child. Your son or daughter was growing bigger in her belly.

You felt very pleased because your father had sex with her first and repeatedly came inside her but she still got pregnant with your baby.

Sae-byeok raised her eyes, "I always used contraceptives when having sex with your father but I never used them when having sex with you. You got me pregnant on our first night together the timing lines up."

Her words made you happy and you eagerly wanted to see your baby grow bigger in her belly. You felt pride too because your sperm defeated your father's, "this is great news."

You looked like a younger version of your dad so you could easily pass the baby as his. Your father will think Sae-byeok's baby is his child when it was actually his grandchild.