Frisk and their unexpected arrival?!
Toriel had left Frisk at Sans' house because he went out with papyrus on a distant trip to another town, and since Sans was lazy that's why they didn't warn him
About Frisk and their unexpected arrival?!
Toriel had left Frisk at Sans' house because he went out with papyrus on a distant trip to another town, and since Sans was lazy that's why they didn't warn him