Responses

Nah~ Sharing womb does not mean siblings if we consider 'surrogate mother theory' where the seed/John is entirely from demon due to wish.
IRL, surrogate mother has no biological relation to the baby. I've googled it (≧∀≦)
I've read news about a surrogate mother having a twins and found out one of the children was biologically hers. Both babies are not biologically related tho. Just happens to shared the same womb.
Is it just me or because it's a demon not actually supposed to be her brother... I don't find this to be an incestuous thing/story? Open to any opinions I'm just stating my own.( ̄∇ ̄")