It's fruitless to try to understand it logically. I'll just say I think the buried Yuyuko is out of the equation. Ghost Yuyuko is pragnent with the myon-half of Youmu because why not. It's actually made of grisly cum and she was able to absorb it into her cunt I guess..
Even if you tell me that you want to have children, it's impossible with our two bodies alone!
Somewhat liberal translationThen what do we need?T-that's... Peni.... I mean... Seme.... Err...Another Touhou M-1 Grand Prix.
[What I want the most is your child!]She conceived.Cough*stroke**stare*What are you making me say!?YoumuAh, That stuff! Those white tadpole looking things!
Mumbling...