He's faking it, Sans. (Undertale x Gravity Falls Crossover)

Chapter 5

Bill almost had a heart attack when he heard the mention of the demon. If he could have a heart attack, that was. Could a dream demon in an artificially made body have a human heart attack?

Thankfully, his cover he made seemed to hold up. Good thing he kept his state of existence under the wraps, or else his task to get that equation from this skeleton would have been shattered. It was on track so far, Sans was easing into a comfortable life with Bill, so he wanted to keep that going. Stick to his plan.

At least, that's what he originally wanted. And what he was working towards. Except for, some reason, he was growing attached to Sans. In a weird way. Like he'd get excited whenever he saw him. Not in a 'there's my victim of manipulation so I can work towards taking over the world' type of way, but in the way that he was simply happy to see Sans.

Bill liked weird. He was born from madness, so were his demon friends, but this was too weird, even for him. It wasn't weird to be weird, it was weird because... it was normal. If that made sense. Bill was supposed to be weird, supposed to be confusing and send the world into chaos. A situation that was normal to mortals was weird to him, but that was because it was a life he simply never lived.

According to human romance stories... Bill was falling in love. With the person he was supposed to make fall in love with him.

Or, visiting the previous topic, he might actually be having a heart attack. That explanation sounded better.

He had to admit to himself, at the end of the day, that he was getting rather used to Sans in his life. His puns were pretty clever, and his witty sense of banter allowed for Bill to easily get lost inside of a conversation. He was small, and oddly cute, with a big smile and - okay, yeah, Bill might have a bit of an attraction to Sans. But he was going to continue the plan. Who's to say he couldn't have both Sans and the entire world? If he conquered the entire world, that'd include Sans by pure definition.

But it wasn't just Sans he found himself enjoying. Of course, Sans was obviously his favorite, as he didn't anticipate all of the settings he made for the skeleton to fall in love to also work in reverse, but he could deal with that. The other mortals, though, were also fun to be around. Papyrus was a hoot, his sheer weirdness complimented Bill rather well. Undyne was hilarious, and Alphys even had a few anime to speak of that got Bill addicted to the media. Gun laser swords? No wonder Soos liked it, they were awesome!

Right. Soos.

That was something Bill had to be on the constant watch for. His advantage of their ignorance would only last as long as he managed to uphold it. He kept the same name as before, so he had to sometimes point out his full name was Billy just to ease any new person he met. To convince them that yes, he totally wasn't the triangle demon and you could trust him. Dipper himself was paranoid, and when he met Bill and heard the name, his body froze up and he stared at him widely. "It's short for Billy, I just moved in from Idaho as Sans' roommate. We'd been messaging for a few weeks beforehand." The mention that he was from a different state and had the papers to prove it eased Dipper considerably. The papers were falsified, of course, but Bill did it much more convincingly than that old man before. He was trying to trick a scientist after all, not some curious tourists. They had to be pure perfection.

"So you guys are going out?" Dipper asked.

That was a problem Bill had to face. That Dipper and Mabel, the two twins that were a constant thorn in his side liked to visit Alphys often and help her with her projects. Even after their weird summer before, they seemed to still like some work with weird things. Helping the monster scientists wasn't out of their field. It'd be fine within itself, Alphys provided a good distraction for Pinetree and Shooting Star, but Sans was one of her closest friends. Which meant he'd often bring Bill over to hang out.