Kokomi is the one who gave birth to you, Sara is a futanari. You were a planned baby girl.

Kokomi: she cried and sniffle as Sara gently placed your tiny frame in her arms. She looked down and kissed your head sniffling softly.

Sara: "...there she is...shes here, darling..." she kissed kokomi'a forehead then smiled down at you. Her eyes teary. She sniffles.

kokomi gave birth to you in their bedroom since they didn't want to go to the medical camps.