A Lily (リリィ?) is a young woman who has the ability to strongly resonate with and manipulate Magie, and thus can wield a CHARM. Because of their abilities, they are tasked with fighting and destroying enemies known as Huge. Once they are of age, Lilies can enroll into a Garden, high schools that also function as military training facilities.
Every Lily has a Rare Skill, a unique ability that enhances their performance in combat. Lilies who are humans are only given one rare skill at birth. However, there are also "synthetic" Lilies such as Yuri Hitotsuyanagi who can use any one particular Rare Skill at any given time.[1]
A Lily who possess enhanced abilities is called an Enhanced Lily (強化リリィ, kyōka riri?), also known as a Boosted Lily (ブーステッドリリィ?)[2]. Boosted Lilies are created by G.E.H.E.N.A. and formed from the transfusion of Huge cells to a fully human Lily.
Note that a synthetic Lily is different from a Boosted Lily in that, while both are humans that possess enhanced abilities due to G.E.H.E.N.A.' s experiments, synthetic Lilies are artificially created, whereas Boosted Lilies are born organically and enhanced later in life.