As a cadet at Starfleet Academy, he studied the Vulcan martial art V'Shan, reaching the level of ahn-was, the highest any Human has achieved. Also at the Academy, Ableen began a romantic relationship with classmate Domenica Corsi.
Following graduation, Ableen was assigned to the supply office at Starbase 74, in orbit of Tarsas III. While there, was able to obtain an isolation suit, then under development at the starbase, and in 2362 used it, and a type-1 phaser, in murdering three Vulcan women on Tarsas III.
By 2364, Ableen had transferred to a base on Berengaria, and there murdered three Bolian women with a laser drill. He actually spoke to Corsi about these murders afterward, though keeping his own culpability secret.
By 2366, Ableen was stationed at the supply office at the Starfleet base on Izar, outside of Garthtown. There, he murdered two women with a type-2 phaser. At this point, Izar Peace Office detective Christine Vale, assisted by Lieutenant Corsi, discovered the connection between these murders and Ableen's assignments, and called him in for questioning. At Peace Office Headquarters, Ableen was able to disarm Vale and put her into a rol-shaya grip and threatened to break her neck. Corsi responded by firing on Ableen with her phaser, killing him. (SCE eBook: Security)
Ableen's death had a profound effect on Corsi, who blamed herself for not seeing his true nature, and questioned her ability to so easily kill the man she loved. On the following anniversaries of Ableen's death, Corsi would engage in casual sexual encounters, though otherwise remained emotionally detached. (SCE eBook: Cold Fusion) This emotional detachment also extended to Vale (SCE eBook: The Belly of the Beast) and others connected with the Izar murders. (SCE eBook: Security)