# Deco: Extending Cherished Physical Objects into AI Companion Agents through Dual Embodiment

arXiv: https://arxiv.org/abs/2605.03882 · HTML: https://mlsanity.com/paper/2605.03882/

## Key facts

- No citing papers in the map yet (data through 14 Oct 2026).
- Builds on 9 of its 68 references that are in the map.
- First posted on arXiv 5 May 2026.

## Builds on (most cited first, 9 of 9)

- [Examining Identity Drift in Conversations of LLM Agents](https://mlsanity.com/paper/2412.00804/) (2024)
- [ComPeer: A Generative Conversational Agent for Proactive Peer Support](https://mlsanity.com/paper/2407.18064/) (2024)
- [MindScape Study: Integrating LLM and Behavioral Sensing for Personalized AI-Driven Journaling Experiences](https://mlsanity.com/paper/2409.09570/) (2024)
- [Mental Health Impacts of AI Companions: Triangulating Social Media Quasi-Experiments, User Perspectives, and Relational Theory](https://mlsanity.com/paper/2509.22505/) (2025)
- [InteRecon: Towards Reconstructing Interactivity of Personal Memorable Items in Mixed Reality](https://mlsanity.com/paper/2502.09973/) (2025)
- [Hear You in Silence: Designing for Active Listening in Human Interaction with Conversational Agents Using Context-Aware Pacing](https://mlsanity.com/paper/2602.06134/) (2026)
- [AI for Proactive Mental Health: A Multi-Institutional, Longitudinal, Randomized Controlled Trial](https://mlsanity.com/paper/2601.11530/) (2025)
- [Conversing with Objects toward Fluid Human and Artificial Identities during Life Transitions](https://mlsanity.com/paper/2601.12589/) (2026)
- [More than Decision Support: Exploring Patients' Longitudinal Usage of Large Language Models in Real-World Healthcare-Seeking Journeys](https://mlsanity.com/paper/2602.14733/) (2026)

## Abstract (arXiv)

Physical objects (e.g., plush toys) can transcend materiality to become emotional anchors and provide companionship. However, these bonds remain one-sided because most physical objects cannot reciprocate. AI companions offer responsiveness and personalization, but typically entail building bonds from scratch. We investigated how AI companions might inherit and extend users' existing bonds with physical objects. A formative study (N=9) informed four design principles (Faithful Identity, Calibrated Agency, Ambient Presence, Reciprocal Memory), shaping our Dual-Embodiment Companion Framework. We instantiated it as Deco to create digital embodiments of physical companions. In a within-subjects lab study (N=25), Deco was rated higher than a personalized digital-only companion on six companion-related measures (all p<.01). A subsequent seven-day field deployment (N=17) showed sustained engagement, higher post-deployment well-being (p=.040), and three key relational patterns: digital activities retroactively vitalized physical objects, bond deepening centered on emotional engagement depth, and participants sustained bonds while navigating companions' AI nature. Dual embodiment offers a promising framework for revitalizing physical objects with AI agents.