What Are The Best Sans X Grillby Fanfiction Plot Ideas?

You know, focusing solely on romance plots for Sans and Grillby feels like it misses the mark. Their dynamic in the game is so ambiguous—a customer and a bartender with a possible history, sure, but the source material gives us almost nothing concrete. That's the beauty of it for writing. I've read a bunch where they're instantly a couple, and it often rings hollow. My favorite fics lean into that mystery. One idea I'm partial to is a noir-style detective story where Grillby's bar is a neutral ground for monster political dealings, and Sans, with his connections and lazy genius, is the only one Grillby can reluctantly trust to navigate a conspiracy that threatens the surface. It's less about kissing and more about the tension of two very private people being forced to cooperate. You could explore Sans's scientific past, Grillby's role as an information hub, all that good stuff. The 'plot' is the case, but the relationship builds in the margins—a shared glance over a glass of whiskey, a clipped warning muttered when no one else is listening. That slow, quiet understanding feels more true to their characters to me than grand romantic gestures.

Another angle that doesn't get enough play is pure slice-of-life, almost anti-drama. The Underground had to have had decades of mundane existence before Frisk showed up. What did that look like for them? A fic that's just vignettes: Sans trying to pay his tab with terrible puns, Grillby silently polishing a glass while Sans naps in a corner booth, the unspoken routine of it all becoming a kind of comfort. Maybe Papyrus drags Grillby into one of his 'human friendship training' sessions, and Sans has to intervene, leading to the first real conversation they've had in years. The romance, if it's there, isn't a destination; it's the quiet acknowledgment that this person, in this specific space, is a part of your weird, fractured life. That stuff hits harder for me than any explicit confession scene.

Honestly? I'm so tired of the same angsty or fluffy tropes. What about a body-swap scenario, but played for actual horror instead of comedy? Grillby wakes up in Sans's bony body, feeling the constant, low-grade ache of his HP, hearing the echo of Gaster's whispers in his skull. Sans, trapped in a form made of fire, has to consciously control not to set everything ablaze, feeling his magic burn in a way that's utterly foreign. The plot isn't about them learning to appreciate each other's lives—it's a frantic race against time to reverse the swap before Sans's form extinguishes Grillby's essence or Grillby's volatile magic destroys Sans's delicate structure from the inside. The tension comes from forced, desperate collaboration, and the 'shipping' is just a grim byproduct of that profound, terrifying intimacy. They've literally been inside each other's souls. How do you come back from that? You don't. It changes everything.