It has now been 19 hours and 42 minutes since the death of Will Solace.
Nico couldn't have felt it.
He couldn't have felt it slithering, crawling, ghosting through the air, the ground, the everything and nothing around and within him.
He simply wasn't happy enough.
And so he continued his patrol of the camp's border, circling Thalia's pine tree. This was when—and mind you, it was around 2 a. m.—Will Solace came running up to Nico, looking extremely tired, and for some weird reason seeming to have a neck cramp. His eyes sparkled; they were really beautiful…Shut up, Nico! Nico told his brain.
"OMG NICO!" Will whisper-yelled. "IjustfoundthisamazingandterrifywebsitecalledTumblrI'vebeenbrowsingforhoursandguesswhattherearethesethingscalledfandomsandfanfictionspeakingofwhichyouneedtogetyourcabinconnectedtotheInternettheHephaestuscabinconnectedmycabinbutyeahomgyouwould—"
"Hold your chariot, Solace," Nico exclaimed, laughing at the older boy's sudden, unexpected outburst. "What were you talking about? Fan-dumb…fans are dumb? And yes, I agree, fans do absolutely nothing to cool down the cabins in the summer. Camp really needs central air-conditioning"
"Nononononono…fandoms," Will said, ruffling Nico's hair as he fake-pouted.
And that was when Nico felt it. As soon as he began to feel happy (Will was, after all, the person who could-although Nico would never admit it-turn his mood around even when he was seriously depressed), he felt something pulling the contentment out of him, as if this…thing…had grabbed hold of pieces, strands of his good feelings and was simply extracting them. Will seemed unaffected. Nico figured that, being the literal ray of sunshine he was, Will would not feel if small coins from his immense bank of joy were taken away. Said person interrupted Nico's mental game of Process of Elimination-Monster Edition.
"They're basically groups of people who are obsessed with a certain book or movie or—"
"Solace, do you feel that?" Nico asked, urgently. The thing was closing in, he was positive, yanking out larger and larger chunks of happiness and soon there would be none left and—
"No, di Angelo, my feels are completely annihilated after this fanfic I just read; half of my OTP died."
"Will, I'm being serious right now, don't you feel like something is literally pulling happiness out of you?"
"Nico, chill. You're dad rules over dead people…and we all know you aren't exactly one to skip around picking flowers. Wait…you haven't been shadow-travelling have you? Those were doctor's orders!" Will glared at Nico.
"No, I haven't shadow travelled since the Parthenos…" Nico muttered distractedly. He had so far eliminated all monsters he knew about. The worst part though, was that Nico had absolutely no clue how to get rid of this monster…or force…or whatever it was. And he was sinking quickly into an unhappy vortex of swirling sadness; this monster had become greedier, moving on from plucking wisps of happiness as one would eat cotton candy to drinking in the meager amount of joy that was left. Somewhere in his sinking pit of despair, Nico realized that the monster would move on to Will, but he had no way to stop it.
Will collapsed. Dead. Nico later realized that once the demon had taken all Will's happiness, there was nothing else that Will could live for. But Nico had never been truly happy between the time Bianca died and when met Will. Living in a world of misery was nothing new to him. But the sight of Will, dead, on the floor beside him, made him let out a sob.
He hadn't cried since Bianca's death.
He couldn't have called for help, in fear of endangering the other campers. He had to face this demon, this monster that had killed his best friend who he knew he loved, too. Nico was furious; he had no idea what this demon had done to Will, but he was determined to make it stop. But how…
The creature fed off happiness. The way to defeat it had to be the opposite. Despair. He'd have to feed it such intense misery that it would collapse in on itself. And Nico had plenty of that in his memory.
He collected it in his sword. Memories of near death and constant depression wandering through Tartarus. The grim certainty that he would never escape that jar, that he would simply eat pomegranate seeds until his life ran out. The feeling of abandonment and betrayal when he heard his sister was dead. And then he channeled the final fireball of grief: Will's death; fresh with feelings of rage, terror and anguish. And the memories. When Will stopped in the middle of a war to tell Nico he belonged and had friends. His three days confined in the infirmary that he grew to love. They way they'd go together to all their camp activities. It was the knowing, the sheer realization that no more of these memories would ever be created, that made Nico want to collapse. But he channeled this, used it to fuel his stream of the-opposite-of-happiness that he directed all around him through his Stygian Iron sword.
When the campers went outside the next day, they were met with the sight of two campers lying next to each other, one breathing and one not.