I see what you're saying, but that IS a good opening to a love story.
The only other time we see Inoue stand up and fight with this sort of look is against that octopus hollow she activated her power to protect Tatsuki from.
She isn't posturing or lying to herself.
This was hard, she knows there could be consequences, but she HAS to do this. To stand up for herself and what she believes in.
There's conflict here, and resolution.
Ulquiorra was pushing her, seeing how far he could, and instead of fake-smiling and rolling under it and crunching herself down like in nearly every single other instance in the series, Inoue slaps him and makes him stop talking and consider her.
He's forced her to drop the dainty, good-girl mask and be her real self, express a real, forceful opinion and be assertive.
"Chads not dead. He's not." she says, and even then her eyes are already narrowing in defiance, in irritation at how flippantly and certainly Ulquiorra is treating the "fact" that Nnoitora killed Chad.
When he tries to feed her she says she's not hungry, when he threatens to force-feed her she stays silent and upright and looks down thoughtfully, then speaks again with quiet confidence:
And this, having nothing more to say than that, seems to strike a nerve in Ulquiorra because he speaks again, worrying at her (to him) puzzling behavior:
"That's enough. It doesn't matter. What do you want me to say? Don't worry? He's still alive? Nonsense. I'm not here to comfort you."
And she says nothing, but now her not saying anything is really bothering him. He doesn't understand and says so:
"I don't understand. What difference does it make weither he's alive or dead? One way or another, your friends will all die soon. On eof them just happened to die sooner than the others."
And this SHOCKS Inoue. She gets a very startled, wait, what? kind of look on her face and now she's staying quiet because she has nothing to say, but for an entirely different reason than before.
"One way or another your friends will all die son. One of them jsut happened to die sooner than the others. You must've known this was coming."
And this is where Inoue feels compelled to speak again - not a defiance but a weak plead "Stop." Because the thing is Ulquiorra is right in a way, and this is a truth she had been rejecting, denying. Her coming here put everyone in grave danger. This realization is starting to set in and she's THINKING about things in a way she wouldn't have unless pushed like this.
Ulquiorra goes on to say she's foolish if she didn't realize that and she's looking right at him and not at all saying she didn't or couldn't have known. She's confronting that realization, that affirmation of a fear she'd had for a while, peeling back that denial that she'd cocooned herself in, telling herself she'd come there for any grand reason instead of a secret hope that everyone would pass the test and follow her, find her worthy of being rescued just like Rukia, and that she hadn't thought of the danger it put everyone in until this moment.
The point at which she disagrees with him, the point at which her expression goes from listening to this frightened anger is when he says:
"...I'd be disgusted with them for rushing into Hueco Mundo like lambs to the slaughter."
She then RUNS across the whole room to slap him.
She's angry and offended and no matter what fault in herself she can accept for having been the cause of all this, her friends coming for her is not something disgusting or foolish and she won't stand for it to be said, and she doesn't make any attempt to hide this.
Inoue lets Ulquiorra see all of her anger and offense, her guilt and fear, and he backs down. Her expression firms on the next page and his turn away from her is slow, reluctant. It takes three panels.
In this scene they both landed a blow on the other that opened up something of the truth of them to themselves.
Inoue had made a mistake coming, but she wasn't going to blame her friends for following or listen to them be derided.
Ulquiorra was moved to fascination with her here and concedes the argument to her. He walks away with an idle threat over his shoulder he clearly doesn't mean and leaves her to be upset and sad as she wishes instead of continuing to force either issue - the food or her friends inevitable death.
And the place where he's going when he leaves is to confront Ichigo.
That puts that confrontation in the light that Ulquiorra is testing the veracity of what Inoue had just asserted.
And Ichigo fails that test on every level.
He tries to leave, he reveals he doubted Inoue from the start and was going into fighting him with no reason, he shows his utter ignorance in thinking Ulquiorra was the primera, then ultimately fails and falls in that battle.
And he's disappointed after.
But also puzzled by Ichigo's similar insistence that Rukia isn't dead and he's going to save her when he tries to leave.
That stood out to him because Inoue introduced the concept to him.
And in the end, he tells Ichigo:
"This is the end for you. Leave this world immediately if you can still move. If you can't, stay there and die. Your quest ends here shinigami."
That one conversation, that one slap from Inoue, struck something so deep in him that it fundamentally changed him.
Before this he would have killed Ichigo and been done with it. With the way he lived, the philosophy's he lived by and the environment he lived in, there was no one reason he should have done anything but kill Ichigo. But now he is moved enough to want to let her friends live if they can. There is no other reason but for her sake that he would spare Ichigo, and he does.
That is an excellent moment in their relationship because it's very gritty and real and transformative for the both of them.
