There’s definitely some development supposed to be happening, but I can’t 100% point my finger to what causes it or why.

His character is written specifically to ask “Is Nikki happy?” and in the beginning he stands down because he thought he did “something she didn’t like”. The full switch happens way later, I suspect after the “rape-scene” when he learned the truth about her father. Why that is, I can not explain, I guess most people would handle that hypothetical situation completely differently, which makes him difficult to empathize later on.

Ian is NOT the most malicious person in the movie because Bear literally rapes Nikki repeatedly. That isn’t to say Ian is a good person, just that there is definitely a worse person in the movie

Look at how their relationship progresses. From the very beginning when she insists on coming back to his house, he is hesitant and uncomforabtle, and only agrees because she’s clearly unhinged and does not want to be alone. He initially gives her his bed and plans to sleep on his couch, until she asks him to share a bed with her. He turns away when she takes her shirt off and leaves his own clothes on. Then she starts making out with him and he is hesitant at first. Finally, the true Nikki is able to “break through” and says “what the fuck?”, and as soon as that happens Bear backs the fuck off and says “you made me feel like I did something you didn’t like”, and fake Nikki regains control, plays it off as a panic attack. Bear is still freaked out and at that point gets out of the bed and sleeps on the floor instead.

After this, we see Bear look on the internet to see whether One Wish Willows might actually work. He finds mixed results and no satisfactory answer.

Then she comes back the next day to apologize for and excuse her odd behavior, assure him that she consented and he did not take advantage of her, and says that she likes him. Not just that, but Bear specifically asks how long she has felt that way and she says “It just happened over time. Started over Christmas”. Which, to me, seems a whole lot like Bear was trying to figure out whether this was fron the One Wish Willow or not, and the fake Nikki’s answer assures him that it was not. It is only AFTER that when they have sex, then a montage of what looks like a few weeks of the two of them being happy together. That ends with the date scene where Ian calls and starts to sew doubts in Bear’s mind again. That night is when he catches fake Nikki watching him sleep, and her behavior starts to devolve after that (taping the door shut, cooking his cat for lunch, we see her standing unable to move while he is at work, etc). He has more conversations with Ian and Sarah that sows more doubt into his mind, and then he calls the customer support line. Which ends with the representative saying “seems like you have a moral obligation to be there for her”. Then he goes inside and eventually they go to the party.

After the party scene he takes her to the hospital, then has a conversation with her about her behavior and tries to pump the brakes and stay the night at Ian’s. She convinces him to stay by guilt tripping him about how lonely she will feel. Then Sarah texts him, he gets to leave, and finally the real Nikki is able to ask him to kill her and says “I haven’t been with you Bear”.

Maybe it’s just that I recently watched Severance too, but it seems to me like the One Wish Willow effectively created a second consciousness that possessed Nikki’s body and pushed down her own. Bear does not know this at any point that he has sex with her, but they also are not shown having sex at any point after he starts doubting her authenticity. Nikki herself later says “I’ve never been with you Bear”. Like Severance, this show asks some uncomfortable questions about how consent can work if two minds share a body. I have seen some people claim Obsession is really about the horrors of Borderline Personality Disorder. I do not agree with those takes, but I do think it’s important to realize that for most of the middle of the movie Bear thinks that Nikki is behaving strangely for natural, not supernatural reasons.

Bear does NOT end his own life on purpose at the end of the movie, either. Bear tries to throw up the medicine to save himself and is only stopped because Wish-Nikki makes her own wish that inadvertently stops him.

He stops when he hears her open the box, not knowing what she is going to wish for, presumably because he wants to stop her.

Hell, the lesson of the movie isn’t even to not wish for love! He could have wished for love! The point is that Bear never actually loved Nikki. Every scene reinforces that he doesn’t actually care about her, that he doesn’t really know anything about her. He doesn’t even care that the Nikki inside of Wish-Nikki is being tormented. He tries everything to make Nikki into the person he wants instead of freeing her. He only cares about himself, and it isn’t even until Wish-Nikki starts literally killing people that he even bothers to actually try to undo his wish.

The very first scene of the movie is Bear opening up about his feelings for Nikki and explaining why he feels that way, specifically citing how she helped him to cope with his grandmother’s death. He isn’t some “incel” or “alpha male” who thinks that women are objects for his desires. He’s a weak, insecure person who has become attached to someone who has already shown him support in the past. He is slow to understand what is truly happening and does not make perfect decisions (he should have called someone else, probably Sarah, to hang out with Nikki that first night. He should have taken her to a mental health professional at some point, etc). If characters were not flawed and made perfect decisions, movies wouldn’t ever last more than 10 minutes. His wish is not to change her, but to be loved by who she is at the time he made the wish.

You say that he “tries everything” to “make Nikki into the person he wants”. What exactly does he try and who is this person that he wants her to be? For the first half of the movie, his actions are him trying to slow things down while the fake Nikki tries to re-assure him. At a certain point, if Bear were to refuse to believe her that would be undermining her own agency and infantilizing her.

You say that he “only cares for himself”, but he seems pretty concerned about Nikki’s wellbeing too. As her behavior escalates he becomes worried that there is something wrong with her. The fake Nikko’s manipulation turns into guilt tripping Bear about how lonely she feels without him, so he tries to accomodate her. If he were selfish, he would have gone to Ian’s party without her. If he were selfish, he would have stayed the night at Ian’s after that incident at the party. We also see that he cares about Sarah, especially in the scene after she is dead where he reads that she had gotten into Luther.

I never said the lesson was “not to wish for love”. I actually said the opposite- the lesson SHOULD not be that because wishes are a work of fiction and that would be a useless lesson. The lesson is that love requires free will in order to be real and fulfilling. And he tries to cancel the wish over the phone before Nikko starts killing people. It’s true that he does not immediately commit suicide himself like the representative implies, but… Well first of all we have another 45 minutes of screentime to fill, but also because he still does not fully believe the wish worked yet. It would be extreme and shark jumping if he killed himself jjsy because some bored and helpful dude working at a call center told him to.