>>283430138
Well, in the first place Devils are pretty much imaginary concepts given an organic body, their outside shell represents the devil concept and their body is organic - all of them have meat, blood and intestines (the place where the soul resides in Asian mythology). While they seem to be completely alien, they are still susceptible to hunger and can consume other beings to get stronger (I wonder if they shit, imagine walking to the grocery store, and you get jumped by the Cockroach devil asking if you have some tissues to wipe his ass) and if what Makima said was correct, most of them require air to breathe (like when she launched Pochita into space). Otherwise they're completely magical (whatever Lazymoto makes up).
We don't know if Bat and Leech actually fucked or was it just some bullshit Lazymoto wrote because he was bored, so we can't conclude whether Devils have reproductive organs.

NOW FIENDS? You can impregnate fiends all you want, they're fair game since they seem to have all body functions of normal humans, YES you could have your OWN POWER and make her give birth to your spawns.
Imagine having a Kon GF