First of all, this isn't yaoi. It's a Chinese manhua.
Second, why does an author need to pander to people who are sensitive to straight couples? While we are free to criticize, we are also free to NOT read it.
No one is forcing you or the dumb ass OP. If you don't like it, don't read. You can take you and your friend's gay fetishizing ass somewhere else.
1. It's weird, because of you.
2. You can't be hating the community you love consuming. The way you're talking right now adds to the weirdness.
3. THERE'S NO YAOI TAG!!!!
4. There are some bi/queer people and ALLY's in here (who are not YOU). who will gladly consume the potential side couple.
5. We don't like straight people like YOU reading queer stories because you guys can't empathize with us. You can't use your brain and open your heart to even try to understand us.
6. You're too insensitive, and that's why it's disgusting.

if demon king and that princess becomes a couple i hope they're shown less in the story like i may as well read a straight manhwa atp