Loreleď didn't have much choice, if she wanted her friends' son to survive, she would have to end the ritual. Not trusting anyone else to take care of her godson, she picked her own finger and let a drop of her blood on the cocoon, hoping he would adapt well to becoming a member of an exclusively female species.
Before the cocoon finished absorbing, she took out her blood stone pendant. It's this world equivalent of a wedding ring, magically made with a drop of the blood from its wearer's spouse. The empress turned it back into blood and let it drop on the cocoon, so the young succubus that would come out of it would also be her husband's biological daughter, not only her own.
Then Loreleď delicately hugged the cocoon, crying while waiting for it to hatch, not noticing it also absorbed her tears.