Spotter

The Spotter (スポッター) position is one of the 9 official positions available to Border agents, one of the 7 directly involved in combat, and one of the 3 a C-rank trainee seemingly cannot work towards. The requirements to be classified as a Spotter are unknown, but Asumi Amakura, the only known Spotter, is also the only one participating in rank battles who utilizes Enhanced Radar, possibly suggesting a correlation between said Trigger and the position. Since none of her Triggers seems to possess any offensive abilities, a Spotter may instead be any A or B-rank agent who has no Triggers capable of inflicting damage in their set, leaving the existence of a ranking specific to this position uncertain.

The duties of a Spotter are unknown. Asumi Amakura's Trigger set is geared towards detection, stealth and retreat tactics, which may mean her role is to keep track of the enemy's position.

Trivia

 * In the military, a spotter is a member of a sniper team who detects, observes, and assigns targets and watches for the results of the shot, also accounting for atmospheric conditions.
 * This would be particularly fitting in Amakura's case, since one of her teammates is a Sniper and another is a Gunner equipped with Eaglet.
 * In the Viz Media localisation of the manga, this position is called "Supporter".