Not slow actually. Not for me anyway. The pacing was well done. No fillers as each chapter moves the plot along. Even better is that the extras are just a nice, chill window to their lives after having an established relationship for a while. Common problems pop up but they're adults who actually communicate.
Someone tell me if I'm wrong (≧▽≦) I've re-read this so many times that I'm now not sure if I'm being biased.
Oh, also. This manhwa explores different versions of love. Platonic love, romantic love, erotic love, unrequited love, even ace representation. If nothing else, maybe put it in 'want to read' and forget it for a while? May or may not be your type so I'm really not sure.

Not interested enough for that many charapter, or should I read them? Idk