Papyrus: You are so lazy, Sans!
Sans: Call me what you want. I got THICK SKIN!
Papyrus: Another bad joke and I'm finished with him!!
Frisk: HAHAHA
Papyrus: We are monsters. The awfulest kind!
Sans: To mess with us takes a lot of SPINE!!!
Sans: Zzzzzzzz.
Papyrus: SANS, WAKE UP!!
Sans: What is it, dude?
Papyrus: A human has fallen from the surface world!
Sans: And you gotta BONE to pick with 'em??
What does a skeleton call their great-grandparents?
A fossil.
Why was the skeleton sad at the dance: Because it had (nobody) to go with.
Papyrus: Nyhe heh heh! I got a swim suit! And it even says cool dude!
Sans: I guess now it says pool dude ;)
Papyrus: SSSSAAAAANNNNSSSS!
What is a skeleton's favorite instrument?
The trom-BONE!
P.S. This joke is very non-original and bad.