Korean manhwa about a guy who cannot fight, but ends up winning every fight he is in I read this Korean manhwa about 2 years ago. I am bad at names, which is why I don't remember the title of the book, nor the names of any of the characters. This is not a popular series, and may not even have an anime. The manhwa is complete.

It has street fights. There are no superpowers whatsoever, as they are all humans. It's all about a guy becoming the top fighter in the school completely by accident.

I believe it takes place at an all boys high school, but there is a girl whom everyone mistakes for a guy attending the school for some reason. There are technically no rules against girls going to that school, though.

The main character is a complete wuss, with brown hair. In the first fight (maybe, not too sure), he pretends to be tough, then a group of people try to beat him up. However, he accidentally beats them all up instead. After that fight, I think pretty much all fights from that point on are 1 on 1, as people try to take him down and fail by sheer bad luck.

Even with all the fights going on, the parents are never involved, though I believe the principle is, and he literally beats up any kids that get into fights.

There's also a less popular remake where he can fight, but he keeps losing to everyone he tries to fight with. Basically, a complete flip of the series.

Feel free to make pot shot guesses, I will look up all answers.
Edit: The series is Transfer Student Storm Bringer. 

The girl in this series has pink hair, and the guy has brown hair.



Maybe you are looking for Angel Densetsu.

In the manga, the main character becomes the top fighter of his school due to luck/accident. As a result, many people from other schools come to challenge him to test his abilities, but he wins by luck as always.

He is totally a complete wuss with no experience in fighting, and he is just ugly.



If the manga above is not what you are looking for, try taking a look at the manga listed below. They also have the same trait as Angel Densetsu where the protagonists are just wusses and win by luck.


Ocha ni Gosu
Gorio
Legend of the Strongest Man, Kurosawa
Bari Haken
Transfer Student Storm Bringer (The girl in this series has pink hair, and the guy has brown hair)