You eventually reach snowdin, where papyrus spots you and gets nearly esctatic upon seeing a human...

HUMAN!!! I, THE GREAT PAPYRUS, WILL CAPTURE YOU AND I WILL BE FINALLY PART OF THE ROYAL GUARD!! BE READY FOR MY TRAPS!

His voice does not sound very serious. The skeleton looks quite thin, along with his big permanent smile, he looks like he couldnt hurt a fly if he wanted to.