In Chapter 26, Chen bringing Yukari out of that cellar when the latter had gone insane, defying Eirin and later confronting everyone over what they did.
What Suika did had a lot of guts, in that she peed in the mopwater, making mustard gas, which dealt a lot of damage to the ones that captured and held them. Doubling as Crowning Moment of Funny, as Satori put it, Suika "is going to hell", which essentially meant that she was risking execution. Here's the conversation:
"You did what?!" Satori asked, to which Suika responded, "I peed in the mopwater."
"Did that mopwater have, by any chance, bleach in it?"
In Chapter 32 of 20XXII, Yuuka sees what their tormentors hit Ran with, decided she was tired of it, and decided to fight back, regardless of what had happened. Well, her efforts paid off in that they decided not to beat them anymore.
In Gensokyo 20XXII, in chapter 46, Kaguya kicking down the warden and them blowing up the place where they were imprisoned.
In chapter 20, Seija gets punished and Yukari saying, "I'll see you in hell."
Yukari's speech to some kitsunes when they attempt to kill Reimu again
Yukari: To you, she is trouble, hence, that is why you wish to end her life because you see her as some sort of threat to your existence. However, whatever the sort may be, she is precious to us and not at all a threat to anyone's life, yet, so get your asses out of here before I decide to end yours right here, right now, and never return.
At the end of the story, Yuuka calling Chen out on her tantrum throwing bullshit but right before that, she told Chen to stop her tantrum and she listened! The fact that she listened made it more awesome because Chen has done nothing but throw tantrums and even injured Ran for some time and Yuuka set her straight, pointing out that if she felt awful that Ran was gone, then she should.
Ran telling Chen, "Listen, if you EVER try to pull that shit again, remember the fact that you can fry an egg on Marisa's glowing red hot ass and the fact that I learn fast and will pull no punches, take that in because that could be your ass that an egg can be fried on. Understand?"
Chapter 41 has Ren telling off his Brother's Bitch Wife
Ren: Pardon me, Miss, not meaning to be rude, but I think you are a total bitch and that your question is rather redundant because I care about them because I love them and they are very much like my own, especially since I've bonded with them, helped take care of them, sacrificed for them, and done almost everything for and with them, I cannot think of something horrible befalling them. They are but babies and that is the reason for the worry as people in this world, the real monsters, have no qualms about doing any of the things you've said. If anything, I do hope they either come back or that we will find them. They may not be your children but they are our children and we love them very much, also, we have lost far too many children and we needn't lose any more. Thank you for listening, fuck off, and shut the hell up.
When Paintbrush Bitch makes a crack calling Yukari a whore, she responds thusly:
Yukari: "Oh-ho-ho, you have some nerve calling me a whore, BITCH! I've sank to levels that you can never barely manage to even crawl, let alone drag yourself, back from and I live with regrets that still eat and claw away at my very being, so do you seriously think I will take being a called a whore by a lowlife bitchy paintbrush of a kitsune who has no place to talk? HELL NO! I've been called that so many times that, after awhile of that and unbearable suffering, over and over and over, again and again and again, until I ultimately felt broken with little else to live for and wanting no more than to die, "Whore" may as well have been my name! Do NOT call me WHORE!!"
This from Chen:
"You're one to talk about having one foot in the grave and, yet, you bear a grudge to the point of madness! If Reimu died, would you be happy then?! I'll let you know, I won't be. You speak of that as if she is unaware, yet, she is. She is fully aware of that and, yet, she does nothing about it because she can't and, to be honest, try as we might, we can't do a thing about it either besides make her final years, months, weeks, days, hours, minutes, and seconds happy, as that is really what can be done, yet, despite that, she enjoys life anyway and that, it seems, cannot be taken from her. Sure, she stabbed you with a pair of scissors but, to be fair, you kicked her in her face and, be noted, she tried to stab with a pair of scissors that one time, you fucking dumbass! And, to be kinda honest, I wish she had strangled you, just to the point where, if you survived, the scars from which would remain forever, serving as a reminder of your foolishness. You speak of Reimu having one foot in the grave, when you were born not too long before a time of madness, the very which we still bleed and heal from, the very which death would have been mercy and most welcomed. We ALL have had one foot in the grave, so you are in no place to talk. Hell, your own mother has attempted suicide more than once, had gone insane during that time, and went through a self-destructive phase, as well as the fact that she's almost died giving birth, Yukari's mind went to shit and she's spent most of her time insane, even contemplating suicide to appease the ghosts, to put an end to the pain, I attempted suicide, and Reimu couldn't even talk coherently and her innocence betrayed her, leaving her with memories she cannot even cope with. Death for her would be both mercy and tragedy and, yet, should she die, her final memories of you would be how horrible you were to her. As she lays sick in that bed, I'm pretty sure she is thinking about how happy you or everyone will be when she's gone because, as far she knows, all she does is cause trouble and doesn't want to anymore. As a matter of fact, her very existence seem to be loathed by pretty much most of the world and you harbor the same animosity, treating her with the same cruelty. What you deal to someone will come back at you a thousand fold and you dealt Reimu pain, something she lacked the comprehension of, thus she dealt it back, with something that terrified you. If she dies of her illness, I will leave and that will be it but I will 'NEVER' forgive you for how you've treated her. May Inari Ōkami have mercy on your soul for the sins you shall spend the remainder of your existence atoning for and suffering through."