[Blood Blockade Battlefront] The Law of Cause and Effect

"When I catch you, you'll disappear~" The boy laughed recklessly. Everything he touched with his fingertips crumbled to dust. "...The cycle of [Cause] and [Effect]? ...Heh... Stop making me laugh. I don't believe in that kind of thing." The boy smiled as he resolutely pulled the trigger. "That was close. Really." The boy said it, but his face showed no concern. "Isn't reality woven from lies? Just like this illusory city." The boy gazed into the distance at the city, its lights hazy in the night, and murmured to himself. "Ha ha, that's hilarious. After all, I'm impossible to solve." The boy spread his arms and taunted the king before him, his expression arrogant and contemptuous. "I only hope that when my sister turns to nothingness, there will be someone she misses. That's enough." Perhaps this was the first time he had ever shown a genuine smile. "The art of life is to care too much about nothing." The boy's gaze was as careless as ever, save for his white-knuckled fingers. "Was my solution... discovered?" Just standing there, he looked so much like a corpse that it was hard not to think he was already dead. "[Cause], [Effect]... Well, whatever. See you in the next life." Liar. Notes: 1. The blurb summarizes the plot. It's fine if you don't understand it. 2. The pairing is tentatively Fan Tou and Stephen A. Starphase. Of course, there's always the possibility of switching sides... 3. The protagonist is an utterly devoted sister-con. Terminally ill with it. 4. Partly related to the original plot, mostly daily life.