There were plenty of things people did not understand about Natsu Dragion.
First was exactly how he was an awesome speed demon one moment, and a crybaby the very instant the boy gets pulled out of his car.
Second, his obsession for a lacrima-powered speed machine.
But the one that always mixed people's minds was how he would always stick with, and never stay away, from the guild's resident demon and torture queen: Lucy Ashley.
Every day, and it is not a mistake to omit the word 'almost', he got several beatings, scoldings, punishments and about all types of obliteration attempts from the blonde woman. But nevertheless, he stayed close, talked to, obeyed and listened to her. It was even a wonder how he still managed to stay alive. They didn't dare question Lucy about the matter either, lest they had a death wish.
But truthfully, to Natsu, the answer was very simple. It was because he promised he would always be there for her, no matter what happened, no matter what the circumstances. He would never leave her of his own will. Because for the girl orphaned from a very young age, a girl taught that she was all alone, a girl who was told she was unwanted, he was her pillar of support, although no one else but the both of them could see it.
And Natsu was more than determined to keep his promise.
So that's why, no matter how many bruises he got, no matter how many broken bones, no matter how many trips to and from the hospital he had to take, he would still stay by her side.
Because he was her best friend.