Negris had always mistaken Little Bone as Ange's avatar, proxy, or projection, so he treated Little Bone the same as he treated Ange, thinking that at worst, Little Bone would ignore him just like Ange did. He never expected Little Bone to actually run away...
The moment it happened, Negris finally remembered that Little Bone was a Silver Skeleton who had always been slippery, ready to run if it couldn't win a fight, and ready to surrender if it couldn't escape. Moreover, since there was no Soul Contact between him and Negris, once Little Bone was gone, Negris had no clue where to find it.
Realizing the severity of the situation, Negris started to panic, "What... what... what do I do now?"
The female mage suggested, "Lord of Knowledge, why don't you come back to the academy with us first? Once we find Mr. Bone, you can leave, or we can ask a priest from the Hall of Knowledge to pick you up?"