If it makes every single character involved in the storyline worse than before, it is a shitty way to implement the threesome/throuple/lesbian relationships, period. I don't know why people try to argue otherwise.
It makes Chloe look like a shitty person for being selfish and not caring about the MC, or Cathy's feelings of which she knows about because she makes jokes about them the entire game, it make Cathy look bad because she doesn't immediately tell about it, she waits after sleeping with the MC to confess. It make the MC look weak for being so passive about it, the only player options are 'I love it', or 'its ok as long as it doesn't happen again'... Why not be pissed about it? You have the options to throw hissy fits for the most random reasons in the game in the past, but when its the most important and the reason the majority of the playerbase plays these games, AKA the relationships, neah, your MC' has a personality change and now he is not impulsive about situations anymore.
Lets not forget about the double standard, change Chloe's gender and it immediately stops being cute and you have a thread on fire, but regardless its a potential LI trying to 'steal' a LI the player is actively pursuing, no matter how you try to spin it. Its just disappointing thats the best he could come up with to set up future poly relationships.
If we are being honest, just like with the forced footjob, the MC's boundaries not being respected in the sub route etc its just the dev thinking if he is ok with something being pushed on them, that means everyone else is, which would be perfectly fine in a kinetic novel, but not in a game with 20 different fetish variables, that get ignored every time the dev thinks some situation is too hot to be bothered by pesky player choices.
I had such high hopes when I played 0.1, but every update sinks further and further, I was saving screenshots to make an in depth review, but now I wonder if its even worth it anymore...