.
Kazuya knew that Mei was more than capable of defending herself if the time came but he was still worried. He had no idea of the current situation on their headquarters nor does he know how much people were actually threatening to barge their way through.
It still has not been confirmed if it was real government official so the security team couldn't kick them out as usual. So Jirou ordered them to stall for time as he was already on his way. The mere fact that someone who was supposed to be an official brought thugs along in itself leaves a lot of room for suspicion.
"Calm down kid" Jirou could feel Kazuya's anxiety. This was the moment that he realized how much place Kazuno Mei had in this boy's heart. "You have to trust in the system and people you have under you"