One was already a Peak Level 3 Human Battle Guard.
He was also a handsome dude with a great physique. Like the other guards, his posture was always straight, as if to imply how confident they were in their abilities as a guard.
Amongst all the guards, One was the strongest. He was even stronger than Roland by a whole level. His perception, and the overall aspects of his body, was already countless times stronger than ordinary people.
Paired with the recent skills and knowledge that Roland bought, One's perception about his surroundings has become even more terrifying.
When he asked Stacey's secret guard on why she was following them, One was already one hundred percent that she was the person who almost made a move at the QP Hotel earlier.
After she denied his question the second time, he asked permission from Roland to attack.
The latter gave the go signal, and One did not waste any more time as he did so as he was told.