Beginning his journey in the Philippines, Yuu plunders an ability for seeking out other users and slowly starts taking the abilities from each user he meets, earning him a reputation as the dreaded "One-Eyed Grim Reaper". At a paramilitary facility that exploits adolescent ability users, he gains an ability to detect those with dormant abilities, using an illness-worsening ability to accelerate the abilities' development in order to plunder them...