[He can think of no legitimate reason for that what so ever. His gaze follows Papyrus's - even like this, part of him is looking for some clue if the flower's location.]

I... I know it's hard to believe, but... he's done stuff like this before. Befriending people, trying to be popular... He knows what kind of stuff he's gotta say for you to believe him. He knows you better than you know him.

[Sans sounds like he's trying to convince someone back from the edge of a cliff, from the level of desperation in his tone.]