Choline Strase holds the rank of colonel and serves as an instructor at the Azami military academy. Her name originates from the term "cholinesterase" (コリンエステラーゼ, *korin'esuterāze*). She specializes exclusively in recovery magic, a discipline where her skills place her among the highest-ranked practitioners within the Kingdom of Thistle.

Her professional capacity involves interacting with Meltfan Dextro, a fellow instructor at the academy. Choline Strase nurtures unspoken romantic feelings towards Meltfan Dextro. She speaks with a Western accent and exhibits low feminine power.