Mernes, a half-demon, half-human general in the demon army, oversees espionage, border patrol, and strategic construction. His origins trace back to early enslavement, later purchased by the Assassin’s Guild, where ruthless training forged his mastery of stealth and combat. By sixteen, he ascended to guild leadership, his childhood scars fueling a vengeful disdain for humanity—a grudge he leveraged to undermine human forces during Echidna’s first invasion.

Distinguished by white hair veiling his right eye and piercing blue eyes, Mernes shrouds himself in a faded green cloak, its fabric often masking his face. His androgynous features enable seamless undercover operations, including impersonations as tavern staff. Though his silence and social unease force reliance on intermediaries for dialogue, he quietly strives to articulate emotions and forge genuine connections.

Guided by Leo, a retired hero, Mernes confronts his anxieties through staged tavern roleplay, simulating conversations to dismantle his communication barriers. Reluctant progress peaks when he confides his traumatic history to Leo, cementing their trust and unraveling his prior scheme to usurp Echidna’s forces for vengeance—a plan discarded after observing her unexpected compassion.

Within the demon ranks, Mernes maintains disciplined rapport with Echidna and gradual camaraderie with fellow generals. As his skills mature, he intervenes in crises like Edvard’s emotional collapses, balancing newfound empathy with lingering social hesitations. His evolution from solitary assassin to tentative collaborator underscores a fragile reconciliation with humanity, though the echoes of isolation still shadow his interactions.