Antag

When Protag and Co-Worker finally appear on Day ???, Antag and Fake Co-Worker are immediately shown to be very animated. In the ending of "Strange Peril," Antag is the only one who speaks to Protag. He introduces himself along with Fake Co-Worker before convincing Protag to let them get on the elevator with them. However, this was just a ruse to switch places with the other pair. In the final sequence, Antag grabs Protag's tie and throws him into the elevator. Before the door closes, he is seen giving Protag and Co-Worker the middle finger with a demented expression.

If you avoid the "Strange Danger" ending, Protag will interrogate Fake Co-Worker instead of Antag, much to the latter's discomfort. To ensure Fake Co-Worker doesn't reveal anything, Protag tries to silence him with glares or by directly interrupting the conversation, but Fake Co-Worker eventually loses patience. It's then revealed that they've both been trapped in the elevator for an incredibly long time. The only unit of measurement they cite for the passage of time is that Fake Co-Worker's watch ran out of battery "months ago." Besides the dead watch, all they have are the scissors Antag found in the ventilation duct. When Protag tricks Antag into handing over the scissors before locking them back in the elevator, Antag screams, "No! No! I'll kill you! I'll kill you!" as he and Fake Co-Worker try unsuccessfully to force the door open.

When another Protagonist and Co-Worker duo first put them in the elevator, Antag remained quiet and withdrawn. On the sixth day, Antag found the scissors in the ventilation duct and clutched them.

On day 34, Fake Co-Worker's attempt at conversation finally caused Antag to snap. Antag punched him while wielding scissors in his other hand, screaming at Fake Co-Worker incessantly. At that moment, their personalities seemed to switch, and Antag now had control over Fake Co-Worker. His unbalanced state is largely due to the fact that he is, technically, a past version of Protag, meaning he also suffered multiple deaths before being trapped in the elevator. Having endured horrific situations and been resurrected nonetheless made him firmly believe they could get out of this.

He maintains a rather neat appearance, almost identical to Protag's, except for his rolled-up sleeves and the complete absence of a tie. Furthermore, his jacket is unbuttoned, revealing a black belt. He always stares intently at Protag.

Antag appears to be very friendly and outgoing. During conversations, he usually speaks for himself and for Fake Co-Worker. He is determined to do whatever it takes to get out of the elevator and offers no more information about the situation than is strictly necessary for him and Fake Co-Worker to succeed. When Fake Co-Worker deviates from the plan, Antag becomes much more threatening, abandoning his affable personality.