Ex is the legendary holy sword belonging to the Princess, and his full name is Excalibur. He is a sentient, talking weapon who was captured alongside his wielder by the demonic Hellhorde. Despite being a sword of immense power that could likely facilitate an easy escape, Ex remains with the Princess in her relatively lax confinement.

In terms of personality, Ex serves as the quintessential straight man to the absurdity of his situation. He is often seen trying to advise the Princess against succumbing to the demons temptations, urging her to resist revealing the empires secrets. His demeanor is typically one of exasperation and constant concern as he watches his master repeatedly give in to the interrogators unconventional methods. While the Princess cheerfully partakes in the delicious foods and comfortable activities offered by their captors, Ex serves as the voice of reason, fretting over the potential consequences of her betrayals, however minor they may be.

Exs primary motivation is to fulfill his duty as the Princesss weapon and advisor, attempting to maintain her honor and protect the interests of the human realm. He consistently tries to prevent the Princess from divulging any information, but his efforts are almost always in vain as her love for food and creature comforts overwhelms her willpower.

Within the storys structure, Ex acts as a commentator and a narrative foil to the Princess. While she is the protagonist who finds herself torn between her duty and her desires, Ex represents the rigid principles of the Imperial Army that the Princess has seemingly abandoned. He provides a running internal monologue, often narrating the series of events and highlighting the absurdity of the "torture" sessions. His function is to underscore how truly unconventional and effective the Hellhordes tactics are, as they have managed to subdue not just a warrior princess but also her legendary sentient sword.

The most significant relationship is, of course, with the Princess herself. Ex is entirely dependent on her as his wielder, yet she often ignores his counsel, leading to a dynamic where he is a powerless observer to her willing capitulation. He has relationships with the demon torturers as well, primarily as a captive audience and an object of curiosity, but his interactions are almost always framed through his exasperated reactions to their success.

Ex exhibits little in the way of character development, which is central to his role as a static anchor in a chaotic situation. He begins the series as a serious, duty-bound holy sword and remains consistently flustered and concerned. His lack of change highlights the Princesss gradual, and perhaps even willing, acclimation to her life in captivity. He is a constant reminder of who the Princess is supposed to be versus who she is becoming.

As a notable ability, Ex is a holy blade of legendary status, suggesting immense power in combat. He is fully capable of speech and independent thought, allowing him to reason with, and attempt to scold, his wielder and captors alike. However, his role in the series is almost entirely passive, and his combat capabilities are rarely, if ever, demonstrated as the story focuses on non-violent temptation rather than physical confrontation.