I think it's the extra from the first volume, but even that was Yu's imagination when the doctor told him if he wants to stop his heat, he'd have to be mated or get pregnant
No there is a raw where kotani said he want a child then it show surgery room and kotani falling asleep with their child
Oh, that'll be great! I guess I'll look it up if it won't be posted here
Found it! According to the mangaka's twitter (@/haruto_info) it should be the Extras if you purchase the manga from Animate (at least I assume it's this one since just as you said, there's operation room in the teaser)
sorry, haruta_info lol
Yes! I'm sure it's the extra for some purchase. I don't remember where i read it, probably hit some raws link people posted. Hope someone will post it here too
Hopefully so!!
Actually there is one raw side stories where they showed the babies but idk where it's from. Probably an extra if you bought something