Duan Yu surely caused many troubles to Murong Fu during his adventures. Throughout the story, Duan Yu gained a few things and Murong Fu lost a few things. Murong Fu was one that wanted power and to be the best, while Duan Yu had no interest in anything that Murong Fu wanted: become king, learn martial arts...

Becoming king:
Duan Yu - Was a born a prince of Dali and had all the riches around him.
Murong Fu - His life's goal ever since he was a kid was to become king and tried so hard to achieve it

Martial Arts:
Duan Yu - Obviously showed no interest in martial arts but ended up learning one of the best by accident
Murong Fu - Worked hard to become the best. (Not sure about this one) However, always ended up getting embarrassed by defeat to the point that he wanted to kill himself

Family
Duan Yu - Had the love of parents around him: his mother and father, uncle
Murong Fu - Father and mother died when he was young and had a pretty sad childhood with his mother always pushing him to restore the Yan dynasty

Love
Duan Yu - Now, this one Duan Yu's got the 'worser' situation. Always finding out that he's the brother of the girls he meet and the girl that he loves, Wang Yuyan, loves her cousin instead. However, he still wins because Wang Yuyan decided to leave Murong Fu and be with him
Murong Fu - Had a beautiful girl that was so faithful and in love with him. Chased her away and then created the perfect situation for her to be with someone else

Duan Yanqing
Duan Yu - Although this is not a good thing for him, it was nevertheless what Murong Fu wanted to be, Duan Yanqing's son. Right after Murong Fu wanted Duan Yanqing to be his godfather, Dao Beifang reveals that Duan Yu was his son.
Murong Fu - Wanted to be son of Duan Yanqing in hoping that Dali will help him restore the Yan Dynasty and is even willing to change his last name

Now this is what I call main character's luck.