What is a third class mentality all about?

Few days back me and one of my friends where hanging out in the market discussing on the new t-shirt which he has purchased from the market some day. Basically I was trying to tease him by saying that he has been fooled by the shop keeper from where he has purchased the t-shirt. The same t-shirt which he has purchased spending 350 bucks was available in just 100 bucks at the other shop. He was getting really irritated by my comments and I was really enjoying it. While having the chat we reached a park where a couple was enjoying with each other under a tree. None of us paid attention to them but were busy in our conversation. I again repeated my comment to him about the t-shirt that these types are available in just 100 bucks. Suddenly the girl came out from the bushes and started scolding us saying that yes I am available in 100 bucks you can also take me with you and added that people like you have a Third class mentality. We couldn't say anything to the girl because she was not ready to listen anything then we switched to his boyfriend and asked him to better make her quite or get ready to face the dire consequences. Then he made her quite and the both went away making a bad face to me. Since then I am not able to understand why she considered us the people having a Third Class Mentality.

Sweet Gabru - Transporter(इस फरेबी दुनिया में ऐसा कई बार हुआ , गुनाहगार कोई और था, गुनाहगार कोई और हुआ)

We are many colleagues in my company. But among them we are 3 best friends in our transport company- Yudhvir, Balraj and My self. Balraj used to work in night shift and we were in day shift. So Balraj used to takes rest in day time at mess. Our mess was located in a domicile area.

There was a girl in our neighborhood. Balraj liked her very much. So we decided to get information about her. One day Balraj and Yudh followed her, She went in a computer center and she was doing MCA from that center and her name was Monika, they also went in to the center and and got inquiry about various courses as well as that girl. And they decided that we would to do MCA from that center.

And we got admission in MCA. But after some days, someone told us that she is already engaged and also decided to marry with him. This was the end of sweet dream of Balraj. After that we decided that "its nothing" and we will to do our MCA complete, in exams Monika always sat next to Balraj.

It was our 5th semester's exam. of Computer Graphics. Due to some reason Monika couldn't have made preparations. So she decided to take help from slips(cheating). Balraj watching her in exam while she was cheating, he refused her, but she told him after just a minute she would through the slip. And she gave slip the to Balraj to through, suddenly an investigator came in there and he caught the Balraj with slip.
We tried to handle the situations but the investigator was not ready to listen any word and he made the case of a cheater on Balraj.

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