Esk is a delusive type vate and is one of the minor deities of Lost Illusion. She appears physically during the events of fiction Chronicles: Concert of the Morning Moon, as one of the handmaiden of Maayaa, along with Eo. Esk wields a gun named Tonsoukyokukon-Indoushin (遁走曲魂・引導心 Fugue Soul Requiem Heart). Her true name is Shoumei (生命 Shoumei).

Esk has pearl eyes and fulvous hair. She reached transcendental state when she survived a long time being constantly violated until she was killed. She symbolizes the unyielding survival spirit, even though the odds are against her.

Esk's name and design are a homage to Desblood 4. She is 162 cm tall and weighs 66 kg.