From War to Science {UNDERTALE}

Failure

                Gaster knew there was no way he'd be able to rest after the past few hours. The stress of needing to save Asgore's life and the rush of succeeding meant his mind was buzzing like mad. He'd be wide-awake for at least several more hours—possibly days, if previous experiences were anything to go by. Going to his home would be pointless; yes, the walk all the way to Snowdin might burn off some of the energy, but not all of it.

So, naturally, he went to the Core. True, the main controls didn't need to be recalibrated for another month or so—and, honestly, he could get one of the workers to do it by this point—but doing it himself right now meant he wouldn't be sitting in Snowdin debating on running the entire length of the Underground. So, thankful he'd kept his ID card in his pocket, he entered the Core and got to work.

He really ought to have been surprised when he heard footsteps come up the stairway behind him. But, honestly, he knew better at this point.

"Whose card did you take?" he asked, not looking up as he examined the temperature gauge for the Core's upper levels. The feet shuffled slightly on the metal floor, and he heard the little clicks of a locket being opened and closed.

"Mom's."

"Mm."

"I haven't done it before!"

"Because it does not work when I am not in the Core." He finally looked up, sighing as he looked down at Chara. "Why are you—"

"It wasn't on purpose, okay?" they said flatly, crossing their arms.

"Er, what?"

"What happened with Dad. I didn't want to hurt him."

Gaster looked at them in surprise, then turned back to the gauge. "I did not say anything regarding what happened with your father."

"Yeah, but you thought it."

"I did not."

Chara huffed, walking over to the railing. "It was just supposed to be funny."

Gaster blinked. "Funny?"

Chara glanced up at him, dark eyes serious. "Y'know, buttercups instead of cups of butter. He'd think he was eating a butterscotch pie, but get a mouthful of flowers instead. I didn't think they'd poison him." They leaned against the railing, looking down at the magma below them.

Gaster sighed as he shut the gauge's case. "You should go home and to bed, Chara. Today has been hard."

"You aren't in bed."

"And when you are an adult, you can also manage stress in unhealthy ways." He sighed and rubbed his skull. "Why are you here? I do not think you would willingly hurt your father, so there is no need to plead your case."

Chara stayed quiet for a long moment, then dug in their pocket and pulled something out. Gaster leaned over curiously as he heard the crinkle of a wrapper.

"Is that...candy?" he asked with a frown. Chara nodded.

"Yeah, chocolate from the Surface. Mom got it for me." They broke a chunk of it off, then frowned and threw it down into the magma below.

"Chara!"

They looked up. "Will it hurt the Core?"

"Er..." Well...it probably evaporated before any damage could be done, honestly. "No. But...if that's from the Surface, then it must be very hard to get, and you should not..."