[It's not as though this is the first collision Papyrus has had since his arrival. Getting so immersed in his surroundings can lead to a certain... lack of spatial awareness. So when Adrien bumps into him, he doesn't respond with frustration or shock, but a friendly chuckle.]

Fear not, human! I, the Great Papyrus, understand your predicament! After all, this is a new world. New sights! New sounds! A well of untapped potential!

[For a skeleton, he's awfully chatty. Amazing, since he doesn't have any lungs.]