Tbh, this is a porn board. The porn is a requirement, at the end of the day. If you just want to discuss it without seeing porn, idk, try tumblr?
That being said, you can talk about whatever you want in the body of your posts as long as it's within the rules and you're posting porn with it. Whether or not anyone will engage you is a different question, but you're free to try and start up convos or even threads if you want as long as there's porn visible. I myself am very open to simply talking about yaoi.
Yes, that is a thing. Everything from adoption to magic babies can be found in some manga or another. You can even find ones that are rather wholesome all things considered.