Ahh, the classic "throw a newbie right into the fire with absolutely zero training and then shame them when they inevitably screw up" routine. Even in manga, part time jobs are the worst.
Not just with part-time jobs, full time jobs can be pretty terrible too, if not worse.
Case in point, something like this happened to me at work. Got very little training for a new position for working out of class to cover a temporary vacancy. I had to deal with a completely new system put in place that was not there when the original person was working the position.
The previous person was moved onto a large project so I was covering. Then, because things were not going well (due to the new system and lack of training I received) the previous person was called in to help a little. After the issue was sorted and we had a debriefing meeting, they straight called me out in front of everyone, including management. "There were some 'inefficiencies' with the new system." Preceeded to say what I did wrong and where things didn't go as well they should have. Of course, they had no idea that I had brought those problems up honestly to management before because, I was undertrained and trying to help sort out the new system at the same time.
Then over the following weeks decided to "fix" things and send them in emails to everyone without talking to me about them first. And it was the wording and tone used as well. To say I was and am pissed is an understatement. Office politics can be a real b*tch.
