Rumina survives in a zombie-overrun post-apocalypse. She lives sealed inside a high-rise with several other girls, diligently performing her assigned chores despite lacking a formal role in the group. Her personality is notably timid and shy, making open connections with companions difficult since arriving. This reserve stems partly from her ongoing personal quest: actively searching for her missing brother, whose disappearance remains unresolved.

Her interactions and approach to challenges blend caution with intellectual curiosity. She possesses fierce loyalty to the group, often prioritizing their security, yet maintains a layer of skepticism. This leads her to carefully analyze situations and potential threats before acting, a vigilance sharpened when internal dangers emerge after a murder. Rumina exhibits deep empathy, frequently considering the emotional impact of events on others and expressing a strong desire to assist those around her.

The collapse of civilization and the constant zombie threat form her world's backdrop. When a brutal killing shatters the shelter's peace, she must navigate the ensuing suspicion and fear alongside the others. The murder investigation's intense pressure tests her relationships and resolve. Her traits—introspection, adaptability to changing circumstances, and reliance on both emotional understanding and logical observation—guide her actions throughout this crisis. Her background, particularly the separation from her brother and the uncertainty surrounding his fate, fuels her motivations and perspective within the group's struggle to uncover the truth amidst surrounding mysteries and dangers.