There was no open door through which?

[October wind]

John Holt “How children fail: fear and failure”

Hi, teachers. I have a question regarding the underlined part. What does it mean exactly?
Yesterday, three young boys were riding the subway to Park Street. They were exceedingly noisy, excited, and rude. They may not have been "delinquents," but they looked as if they could have been, and certainly as if they wanted the rest of us to think they were. The sudden contact with them was shocking. They seemed so far from what we are used to in people, so close to wild animals- but that is a libel on animals. It was hard not to feel that there was no open door through which they could be reached. About them in the car was an aura of stiff and anxious resentment, which they seemed to recognize and enjoy. People were mentally drawing their skirts and coattails aside.

 

[teechar]

that there was no open door through which they could be reached.

... that there was no way of communicating with them ... that there was no way to make them see sense.

 

[Skrej]

Note here that the 'open door' (or lack thereof) is metaphorical.

 

[tedmc]

People were mentally drawing their skirts and coattails aside.

I have problem understanding the last sentence too.

 

[teechar]

People were mentally drawing their skirts and coattails aside.

People on the train were cringing and mentally distancing themselves from those teenagers.