first of all, yes it's definitely a romance!
While up to episode 20 you can still speak of a very intimate friendship/brotherhood (with many subtle), this line is crossed at the latest from episode 21.
Because what happens then can no longer be other than a love affirmation, because you have kisses, cuddling, dirty jokes and even a confession on the beach and thereby the series goes very tame but still further than some KBLs I've seen recently.
And the relationship itself is probably one of the most romantic things I've seen lately, as you really see two soul mates who would give anything for each other.
But just in the middle are a few lengths and a few plots that are not bad in themselves, but could not fully convince me, such as the story of Wu Bis's birth mother or the girlfriend of Wu Bi's brother.
Apart from that, family has a special place in this drama and especially the scenes with the chosen family of the two with little Dua are always very heartwarming.
All in all, "Stay with me" is a more than positive surprise and I personally like it better than the other version "Addicted" but I don't know if it lives up to the current hype.
Apart from that, I'm not that happy with the ending, even if it is the technical end of book one, especially because a second season is not guaranteed.
And also that at the end of another more explicit version with extra scenes should come out, I'm happy of course but I hope the whole project does not fall victim to censorship before.