My 2 star rating is relative to the ability of the dev. Devorny is certainly competent at writing good characters and dialogues. There is a good level of credibility and realism. That is why the ridiculous hook of the NTR plot does not work. Obviously it would be easy for the MC to expose the antagonist and get him out of his family and girlfriend's life. He just has to show the direct messages that the antagonist sent to him ! His family and girlfriend would be appalled and would want nothing to do with the antagonist.
You could counter that oh the MC doesn't want them to know about his past with the antagonist. To that I say he can select wich text he shows, but even then how can wanting to avoid some embarrasment from his past justify letting a convicted drug dealer seeking revenge, enter his family and girlfriend's life ?
The suspension of disbelief is too hard because Devorny doesn't write the MC as an idiot. It's too hard because the whole rest of the dialogues and behaviors are realistic and credible.
It's like you forgive a dumb and fun action movie for being dumb, but if you have a smart story an incredibly dumb and unbelievable plot twist can ruined it.
From a personal taste standpoint, I dislike NTR through the bull. I like the teasing coming from the girlfiend. The bull is just a stuntcock for the kink I enjoy with the girlfriend. I like domination and humiliation coming from the women, not the stuntcock.
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I have edited to 3 stars because I think my 2 stars was too harsh