What was clear - No pregnancy on Koishis part - Child had no third eye
What was not clear - How did Koishi lactate when breast feeding? - Child has no horns as an Oni-baby? - How did she persuade it was hers to begin with... Waiting for translation
2nd Panel... the Oni-mom looks almost like Suika, if she gets slightly bigger horns with ribbons (even her hair would match due to not being visible enough to be different)
The real parents were shortly found.Looks like they turned their eyes away and some mischievous youkai took the opportunity to kidnap the baby.They're oni.. I guess babies don't have horns.This is a nice scene so stop making those jokes.Koishi.....I thought it was the child of my beloved sister and I, so I loved him....I wonder if our mother felt that way.If they have, it must hurt during the expulsion, right?Yeah.....!To think I'd finally became attached to something...Isn't it great, Koishi... You understand mother's heart.This experience shows that a time will come when you'll be useful.