I’m pretty sure it’s bc as stated in the earlier chapters and we can also see that when they started developing animal characteristics they gained female parts as well, so I’d assume that’s why he can produce milk
But a regular female cow doesn’t just produce milk..it’s the same as human breasts for a woman, they only rlly produce milk once they have a child for nutrition
This is fiction.
It doesn't matter what a normal female cow in our reality would need to produce milk. The story isn't set in our reality. He can produce milk quite literally because the author said he can. That's it.
I’m more confused on why tf mister sir is producing milk, when he has no reason to…unless he gave birth to his son but then who's the father and how long have those animal characteristics been around for bc that kid is like 7-9..but if he didn’t give birth to his son, why and how is he producing milk..idk why I just now realized but yah /genq