Rex found what Serevan was talking about incredulous.
Had it been the subjects of the Zahara Consortium, who were spooked by his sudden arrival, he would have understood. Someone with a reputation like him—coming to visit the kingdom was not something ordinary, and it was understandable for them to be scared.
However, that was completely different for someone in Serevan's position.
He's a ruler, he should've acted like one.
For Rex to come here on his own, albeit through sneaking—it should show that he came here in peace. If he wanted to declare war or even bring trouble to the kingdom, he would've done it first before coming to meet them.
In this case, Rex shouldn't have to tell it out loud to Serevan like this.
Realizing the dynamic, Rex averted his gaze toward Serevia who was still silent.
So you're the real ruler, your brother is only a puppet to have an intimidating persona.