As per usual MDL comments are all about how cheating is THE. WORST.
And yep, I completely DISAGREE.  This is a call to check your internalised biases.

I suspect this movie was made to challenge our perception of who can be a victim.  When it comes to intimate partner relationships, typically females are the victims of abuse, and males are the perpetrators (worldwide crime statistics supports this BTW so don’t bother with the “not all men”).  In this movie, the roles have been spun.  It challenges your internalised biases.  Can you empathise with a male, who is stuck in these abusive relationships, or do you see him as a perpetrator of abuse, in the form of cheating? Can a female be an abuser?  The answer is OF COURSE.  But can you see it here? In light of the recent news about Gisele Pelicot, (look her name up if you don't know, I implore you!) I would have hoped that viewers would be more empathetic; and capable of identifying the victim - the ML - and the perpetrators - ALL of the female love interests!! Clearly we need to keep trying!
 
In this current social environment where EVERYTHING has to be compared and categorised to the nth degree, I will bite and rate the toxic behaviours...Emotional abuse, co-ercive control, physical abuse like drugging food and water, MUCH WORSE THAN CHEATING.

******SPOILERS AHEAD*******

The first love interest Pai Chia Chi, makes clear, her co-ercive control, from the moment she sulks about him lying on the bed in his clothes. And confirms it with her list of rules.  My question here was, "What trauma is part of his character, that stops him from RUNNING at this moment?!  For me, that is the main issue in this film:  The male lead character is not developed at all.  He is a frame upon which the abuse is perpetrated. But maybe that is a deliberate choice by the filmmakers, to leave it up to us to figure out!

As my first thought exercise; if you reframe the narrative here, from a perspective that males and females can be friends (something I absolutely believe to be true, when the people involved have ANY level of Emotional intelligence EQ), then his going to meet his old schoolmate to provide support when she is asking for it, is being a kind person. Yes the woman (Lin Ai Hsuan) he is meeting is problematic, but I’ll get to that.  Where it goes awry for him, is that he lies to his partner about who he's meeting. However this is a choice made from the knowledge that, if he tells her the truth, his partner will abuse him emotionally.  I would argue, he is defining himself as an emotional cheater, because acknowledging the reality, that he is the victim of abuse, is too devastating to comprehend.

***Here's facts:  the ONLY way to safely deal with an abuser, is to be STRATEGIC****

He is being strategic in the information he provides to his partner. And by participating in this emotional relationship he is creating an escape route for himself, even if he is doing it somewhat unconsciously. You can also see how, every time he questions anyone about his situation "Does your partner check your phone?...,"  he is gaslighted back into the relationship.  This is also the case during his relationship with the 3rd love interest - when he expresses concern about Kurosawa, "Dude she brings you lunch, she's the perfect girlfriend."  Conversations like these are very true to life.  Victims of domestic abuse, are often told how great their relationship or their partner, appears to be from the outside.  And when they do finally leave, everyone says “What took you so long to leave? Why did you stay?”  If you are here saying, why didn’t he leave when she did blah blah blah…check your empathy and your bias.  It is NOT THAT SIMPLE.

When he is ready to escape, from relationship one, she deploys her heart condition. Her heart condition and hospital visits are text-book co-ercive control.  I am not convinced in that scenario, that it was even real. It may have been real in earlier parts of the story, but right then there is no evidence she’s been to the hospital. She uses it to keep him under control. His escape is only orchestrated by the insertion of magical realism in the form of the white rabbit.  I am sure there is a whole lot of underlying meaning and symbolism in the choice of this character, but I just can’t be bothered here…

For the second love interest, Lin Ai Hsuan, it's all red flags. We got a sense of her being problematic, when she emotionally manipulated him into meeting her in the first place.  But she tells us herself, in a very clear manner with the line "I really wish I could meet someone who was willing to make changes for me..."  NOPE! You should wish for someone with whom you can be yourself, and whom you fully accept as themselves.  That is what unconditional love actually is.  You be you - no conditions (no rules or requirements) Wanting someone to change for you, is again abusive.

Now for my second thought exercise; If Ai Hsuan were of the same gender as the ML, I would argue, no-one here would call it an emotional affair, and yet it still could be.  Just because it's someone of the same gender, or generally someone with whom you have zero prospects of a sexual relationship, if you are investing ALL of your emotional life outside of your relationship, and into your 'friends', that's an emotional affair.  The fact that this relationship doesn’t evolve is a relief to me, not because of the perceived cheating, but because we are spared the exposition of his further abuse.

And now to the third love interest, Kurosawa…the most terrifying of all.  She too exerts exceptional control over his life, with daily meal delivery, changing his household items and bedding,  choosing his toiletries for him.  ALL of this is disturbing.  And when we learn she is drugging him, it is utterly horrifying.  THIS should be the moment when everyone wakes up and reframes the whole movie into one about abuse.  In light of what happened to Gisele Pelicot, SURELY everyone can understand this!?! Please. Understand!

The idea that as some have claimed in the comments, he gets his just deserts at the end, is utterly horrifying to me.  In my opinion, he has done absolutely nothing to deserve any of the abuse.  But also, in my opinion, there is nothing that you can do, that deserves abuse.  This challenges the framework of what makes a “good victim”.  The victim being good or otherwise, is irrelevant.  They are a victim!  The fact that in this, the victim is male, challenges people’s perceptions. This is evident in the comments. I think that it’s just that these biases are so internalised, that it is hard for people to recognise.

And now for my third and final thought exercise: One of the ways to question your biases is to consider the idea of a “good perpetrator”. There is no such thing, but we create them all the time with statements like “he was a good, upstanding citizen…this will destroy his life.”  The dialogue around this movie, centres the character Pai Chia Chi, as a “Good Perpetrator.” Her abuse is framed as ‘quirky’.  But I challenge this.  She is an abuser, pure and simple.  Nothing about her character, makes her abuse acceptable.  If you are willing to control someone’s life, limit their personal freedom, create fear, (even if it’s just the kind that means a person is fearful of telling you the truth), then you are a perpetrator of abuse.  It is not love, it’s control.  The person you are controlling is an object to you, set to serve you and your needs; not an autonomous living, breathing person, of their own needs and wants.  Exerting you will over another, in any way, is abuse.  

Maybe you've watched this from a much less invested perspective, but my reality is, I can't unsee the abuse written large here.