Kelsey is an NAUS “Area 4” captain and combat instructor whose superb fighting skills are renowned throughout the NAUS Marine Corps. Intimately familiar with the human body and its weaknesses, she strikes her opponents with precise, deadly blows in the shortest amount of time. Her stringent teaching methods terrify her students, yet in the end would always produce excellent results. Although Kelsey is a foreign recruit from Europa, she is often invited back to NAUS homeland headquarters to train elite spec-ops.

凱爾西是NAUS海軍陸戰隊在「第四區」的其中一位隊長兼格鬥教官，精湛的格鬥技術在整個NAUS海軍陸戰隊中都赫赫有名。她熟悉人體構造和致命弱點，能在最短的時間內，以快速、凶狠、精准的打擊使對手失去抵抗能力。用最少的體力和行動，打出最有效的攻擊，這嚴苛的考核標准，令每位學員都被折磨得苦不堪言，但效果出眾。雖然凱爾西是在歐洲被招募，但經常會被邀請回NAUS本土總部訓練精英特種作戰人員。