The robber is in stressed condition (like Miharu's observation, it's probably his first time). He's histerical and not processing what other people is saying.
Only later when he dropped his knife and calmed down a little, Hiyori attacks with asking him to listen to her request (making sure he listen now), before asking him to stop.
About the organisation, it would be descibed later, in two parts. First about the history, and then about its working.
The second part can be scary, although not in the usual direction.