Cosplay change a person?

??? What is this video about?
Its not a MV, but a video more look like an advertising.

story about two boys
阿仔，Otaku宅男一个，脑袋里除了动画，还是动画！非常不受班上同学欢迎。
Ah zai, an otaku, his mind only anime, not fav by his classmate.

阿闷，和他做朋友就是西北的闷，内向又自闭！做什么事都没自信。问他十句回一句。当我透明的啊？
Ah mend, making friend with him is ultra bore, ask him 10 question only answer 1, do everything also no confident.

One day, they saw magazine got the cosplay competition, then they decide to join.

Title is "Cosplay 改变一个人" (Cosplay change a person)

altot this story is fake, but in real life, many cosplayer also change a lot after cosplay, example...more confident to themself.