…I don’t know if I can ever let Papyrus into the Royal Guard. Don’t tell him I said that! He’s just… well… I mean it’s not that he’s weak. He’s actually pretty freaking tough! It’s just that… he’s… he’s too innocent and nice!!! […] I could NEVER send him into battle! He’d get ripped into little smiling shreds. That’s part of why… I started teaching him how to cook, you know? So, um, maybe he can do something else with his life.
This first meeting didn’t really go how Sans pictured it, haha. While he’s making progress towards his normal unflappable cool demeanor, he’s not quite there yet. Undyne caught him off-guard so many times that he just couldn’t find his footing again very easily. These kind of things take practice!
Undyne is manifesting/unmanifesting spears throughout the conversation when she’s bored or wants something to do with her hands, mostly.