There are some people in this world you are sure you will never like, its like instant mutual hate. One look at the person in class or around in the campus and you know that you have made an enemy for life. Throughout my 18 years I met two such people, and surprisingly both are guys.
There is something different about hate-at-first sight and gradual hate. When you hate somebody gradually, after getting to know them first, you can just stand their company. You try your best and be civil with them. but when its hate-at-first-sight there is barely any pretense of civility, you ignore that person completely and don’t even acknowledge their presence.