## 2 Theoretical Background and Hypotheses Development
### Organism (O): Human-Social Robot Relationships
#### Trust with MOCCA (TRS)  
Trust lies at the core of human-robot relationship formation [72]. It is a psychological state characterized by an individual's willingness to be vulnerable to the actions of another party [73]. In HRI, trust is defined as the belief that a robot's actions are reliable, predictable, and trustworthy [74; 75]. Prior research shows that trust by humans towards robots is important because it influences the outcomes of HRI [76; 77]. One such outcome is the formation of parasocial relationships, which are viewed as emotional bonds between users and robots [78]. Trust encourages users to emotionally connect with MOCCA and attribute human-like qualities to it. When users trust MOCCA, they are more likely to view it as a relatable social partner rather than just a programmed machine, thereby promoting the development of a parasocial bond. This psychological state of trust emerges not only from evaluating MOCCA's performance but also from the perceived sense of reciprocal engagement during interactions. Trust in robots can be categorized into two main dimensions: cognitive trust, referring to an individual's confidence in the robot's capabilities and reliability, and affective trust, which reflects self-efficacy based on emotional responses to the robot's behavior [79; 80]. Affective trust is rooted in the emotional connections that individuals form with robots [81]. Social robots like MOCCA, designed with anthropomorphic features and emotionally responsive behaviors, can foster affective trust by creating a sense of emotional resonance. This allows users to perceive MOCCA not merely as a functional tool but as a relatable social partner, capable of evoking feelings of comfort, companionship, and emotional support. Research suggests that individuals tend to attribute human-like moral expectations to social robots [50; 82]. When MOCCA is perceived as a morally responsible entity that aligns with human ethical values, users are more likely to develop stronger affective trust and a deeper emotional connection in their interactions with the robot. By contrast, cognitive trust is grounded in rational evaluation, where individuals assess a robot's competence, reliability, and functionality based on observable performance [81]. Users are more likely to develop cognitive trust in MOCCA when it consistently provides accurate information, responds appropriately to commands, and performs tasks with precision. However, if users perceive that MOCCA's responses are entirely pre-determined, they may doubt its ability to truly understand their needs. A high level of perceived dependency may lead users to regard MOCCA as a mechanical tool rather than an autonomous entity [83], reducing cognitive trust. Research has found that individuals tend to trust autonomous agents more when they demonstrate a degree of self-governance, rather than appearing as an extension of pre-programmed instructions [18]. Beyond concerns about autonomy, information privacy risk represents another significant challenge to trust [56; 84]. As a social robot designed for personalized interactions, MOCCA continuously collects, processes, and stores user data through its AI-driven systems and conversational memory. While these capabilities enhance MOCCA's ability to deliver adapted responses based on user needs and improve user experience, they also raise concerns about how personal data are managed, stored, and protected [85]. Privacy concerns are not limited to data protection but also extend to psychological and social privacy, as the presence of an AI-powered social robot in private spaces may lead to perceptions of constant monitoring [86; 87].