This novel can be summarized in three sentences:
Scum top abuses tr*sh bottom.
tr*sh bottom loses his heart completely and leaves scum top.
All of a sudden, the scum top comes to his senses: Oh, I’ll look for the next one then, bye.
Hold on — Where’s the agreed abuse for the scum top? What happened to the promised transformation of scum top into a loyal dog? This isn’t how the script is supposed to be!