Parasite

I do not know any bookish definition of Parasite. When I hear this word, I can only think of few fictional themes, where a little insect come and takes over the brain of a human body. It takes away all kind of empathy. Instead, it fills its emptiness with greed, violence and numbness. 
I have always seen a parasite like this lurking around our society, in our bloods, in our thoughts, and at last, it starts to pollute our feeling to our loved once. 
For me, that parasite is, Corruption. It sounds familiar, right? How can it not be, when you live in a country like Bangladesh. One might think, what so bad about corruption, how can it be related to parasite. Actually, it's related to every single way.  Well, corruption doesn't seem to be so bad when you can get a heavy advantage by just giving a little amount to a particular person, which we consider as "Bokshis". It might feel sweet to get some extra advantage, and it feels so small. Like" Doing it for once shouldn't hurt", right? No, It all start like this, only once at a time. We open the door. Then before you know it, it comes and bites our blood with it's heinous poison, And little by little, it points it's attack to our brain.  And we welcome it with a bright smile. And in return, we sell everything that once belonged to us, morality, love, empathy. Everything that makes a human being a human. And little by little, it starts to take over our brain. And when it takes it all, we wonder, what went wrong. We don't notice it until it turns people around us into a parasite itself. We think, how one human can be so bad. And when we think we should get rid of that parasite from our society, it's already too late. The parasite can not be removed without removing the head. And when we understand that, we don't have what it takes to remove the brain. We choose to keep it, pass it to people around us, to our next generation. And the society becomes a violent bloodbath while the parasite laughs at the corner.