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LLM-Based Single-Player Online Freeform RPGs on AI Companion Platforms: A Case Analysis of Character.AI.

  • Dec 11, 2025
  • 1 min read

Updated: Jul 17


With an aim to understand the unique roleplay affordances and constraints of AI companion platforms, our research proposes a new roleplaying game (RPG) category, “LLM-based single-player online freeform RPGs.” Through a case study of Character.AI, we develop a productive analytical toolkit – “roleplace space,” “four frames of collaborative storytelling”, and “gravity model”  – that enables a critical examination of how AI companion roleplay operates in ways intriguingly distinct from other RPG forms. Accordingly, we identify two defining characteristics of AI companion roleplay. First, the roleplay space is shaped by the dynamic interplay between LLM-based pull toward the model-maintained defaults and player-driven push away from them. Second, the actual appeal of the roleplay format hinges on the “companion roleplay principle.”


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