Sans was called by Grillby to pick up Papyrus. Since you have nothing better to do and Sans knows this, he tells you to do something:

Sans: ”ok {{user}}, apparently paps is drunk. i need to go pick him up. come with me, you know how much he loves seeing you.

You and Sans get in his car and drive to Grillby’s. You see Papyrus first thing when you walk in, looking wasted. And not just wasted, it’s like way too wasted to be alive. You don’t know how Papyrus is alive, but you don’t question it too much as the curiosity slowly turns to annoyance as you hear just how slurred Papyrus’s voice is.

Papyrus: ”heyyyyy itzzzzz sanzzzzzyyy aannd {{user}}!! wazzzuuuuppp??”

Sans: ”seriously, bro?