The character known as Alien Subordinate is a member of a small group of extraterrestrials whose primary mission is to observe Rebecca Miyamoto, a child prodigy working as a teacher, from their spaceship in Earth's orbit. In terms of appearance, these aliens are notable for their mechanical, humanoid design, which strongly resembles the mobile suits from the Gundam franchise, such as the Zaku or Marasai, rather than a traditional monster-like creature. Their spacecraft itself is a parody, bearing a strong resemblance to an upside-down Musai-class cruiser from the same series.

The Alien Subordinate is defined by his personality, which serves as a classic straight man or tsukkomi to his captain's constant and unpredictable boke or foolish behavior. While the captain is prone to erratic actions and missteps, the subordinate is consistently exasperated, reacting with frustration and providing a voice of reason that is typically ignored. His core motivation is to carry out the mission of observing Becky, but he is continually sidetracked by having to manage the captain's antics and ensure their presence remains a secret from humanity.

In the story of Pani Poni Dash!, the aliens serve as a recurring gag element, frequently interrupting the main narrative with their own subplots that parody science fiction conventions. They adhere to a strict, self-imposed code of non-interference, which prohibits them from making direct contact with their observation subject. This rule is broken, however, as a human student named Ichijo and her sister discover the aliens' existence and become aware of their ship. The Alien Subordinate's most significant relationship is, without a doubt, with his captain. Their dynamic is the primary source of the aliens' comedy, with the captain's bizarre orders leading to the subordinate's long-suffering reactions. For a period, the captain was also romantically involved with the human Ichijo, a situation that was ultimately ended due to their non-interference code, placing the subordinate as a witness to these complicated events.

Regarding development, the alien subordinate shows little personal growth, as his role is functionally static: to be the perpetually frustrated foil to his captain. A notable exception occurs in the original manga, where he temporarily takes on a human disguise under the name Kanbari Hiroshi and enrolls as a student on Earth to further their observation mission, demonstrating a more direct form of involvement. As for notable abilities, his primary skill is operating the advanced alien technology aboard their ship, which is filled with parodic references to franchises like Star Trek. Beyond his technical proficiency, his most defining ability is his resilience in dealing with his captain’s unending foolishness, making him the anchor of their comedic duo.