The Love and Breakup Letter Method (LBM) is a valuable qualitative technique for exploring consumer-brand relationships, but its dichotomous nature may overlook nuanced consumer sentiments. This study proposes a modification to the LBM by introducing an “intervention letter” category, allowing participants to express a desire to contribute to product or service improvement. We applied this modified method to investigate customer relationships with service robots in the hotel industry. Findings reveal a significant preference for the intervention letter, highlighting consumers’ active engagement and desire for co-creation. Linguistic analysis further distinguishes the letter types, with intervention letters demonstrating a balanced, task-oriented approach, characterized by a high analytic score and less self-focus compared to love and breakup letters. This modified LBM offers a more comprehensive understanding of consumer experiences, particularly the desire for constructive engagement, and fosters deeper connections between consumers and brands, benefiting both researchers and industry practitioners.