The city was a large and prosperous metropolis. It had grown a lot in the last few months, thanks to the help of a blonde woman who came a few times. She helped them dig for a new subway, she brought fresh water using her ice spells and shaped the land to make it easier to build. When the two sisters appeared, no one was afraid, but they were a bit surprised. The blonde woman was taller than she was last time she came, and she was with an even taller redheaded woman. They were both beautiful young women of similar build, curvy but thin.

Lina was surprised, too. When they arrived in the city, she noticed her sister was smaller than she was - more than usual. She was a full head taller and more, her sister's head only reaching the middle of her torso.  She also noticed her sister had the same surprised looked.
-What's up shorty? Something not like you expected?
-This is strange... and interesting. I wasn't this tall when I was alone, and you're taller than me. My guess would be that the height depends of the user, or the will of the user activating the dagger. I was smaller because I came to help, and Tresdin was bigger because she wanted to do... those terrible things. Which means... Sister! I won't let you harm them!

-Relax, relax! You don't have to jump to conclusions like that. Why don't you show me around, that way I know what to avoid. I promise I'll be careful.

Of course, she had no intention to be careful. As soon as Rylai had turned around and started carefully walking and showing the places to her sister, Lina's mischievous personality took over. Acting as she was unaware of what she was doing, she slowly and deliberately brought her naked feet down on people in the streets as she followed her sister. She tried not to crush them right away, preferring to feel them writhing against her feet. There was something exciting about feeling them struggle and die simply because she walked by, while also looking innocent to her sister. Wanting more, she acted as if she was losing balanced and planted her right foot down on a small building. By her estimate, she had probably killed a hundred people in that building just by being 'clumsy'. The feeling of the crumbling building under her feet was delightful : the crunchy feeling of her sole compacting the structure and its inhabitants into the ground was so satisfying, and it made her feel like a goddess to them. She killed them just by walking around a little bit carelessly, she was getting pretty excited about what she could do if she was really trying to crush them.

Her sister started turning around after hearing that. While Rylai was turning , Lina flicked her fingers behind her back, setting a nearby college on fire where Rylai was no longer looking

-Sister! Look at what you've done!

-Hey, you can't blame me for tripping. You should be watching where you are going, something caught on fire where you were going, you must have stepped on something yourself.

Looking back, Rylai saw the burning building and knew better than to blame herself for it.

-You bitch! I know you did it, and you know I can't just drop a huge block of ice here, it would just make everything worse! Fix it!

-I didn't do anything, and it's not like it's my problem; it's your city after all. Besides, it's not like I can make fire disappear. You'll just have to find something liquid to put on that. Eh, since there doesn't seem to be any water around, you could always piss on it.

She didn't think her sister, the pure maiden, would do that. To her surprise, her sister's frown turned into an uncomfortable expression as she opened her robe and removed her panties, slowly placing them in an unoccupied placed. 
"I'm sorry everyone, I have no choice. There's no way you can put out a fire this big. Please move out of the way for you sake."
Squatting in front of the college, she opened her legs and spread her vulva with her fingers. Aiming at the fire, she closed her eyes and let herself go, not wanting to see the devastation she would cause.
Lina watched intently her sister. Seeing her remove her clothes wasn't without effect on Lina : Rylai was beautiful and young with blond hair and a perfect silhouette, a pure and innocent woman. As if the sight of her body wasn't arousing enough, she squatted and exposed her intimate parts and started peeing in front of her. Lina quickly removed her clothes as well and revealed the stiff cock between her legs. She took it in one hand and stroked it as she enjoyed the show. She watched the torrent of yellow liquid fall and hit the fire, but she was more interested in what was happening around. Her sister was so shy she had closed her eyes, but that meant she wasn't aiming so well, so her urine was splashing everywhere around the college she was aiming at. People around the building were being washed away by the current. Some were being overwhelmed and were dragged under, drowning in it. She figured everyone inside must have been living a similar fate. Without enough time to react, they were stuck inside where most of her piss was landing, the rooms getting filled at a high rate. The people who weren't close to an exit were trying to swim their way out, but the level of urine quickly reached the ceiling. They clawed at the ceiling and walls as they fought for air, but all they could find was the foul, acid taste of Rylai's urine filling their mouths and forcing its way into their throats and lungs, choking and drowning them. The thought of a sweet innocent virgin murdering hundreds of people by peeing on them made her extremely hard and excited, she lusted for her sister's body now.