Lucy Heartfilia is abused by her father. This is because Layla left him. He worked a lot and it stressed him out. So he became a drunkard, and they would find him passed out, surrounded by beer bottles almost every night. Layla got tired of this and left the two of them. Jude was lost. He started to beat Lucy.He said she reminds her if him. She is a spitting image of Layla. Lucy is a depressed person with anxiety. They moved to Magnolia and Lucy now attends Fairy Tail high.
Natsu has never had a good relationship with his old man either. He wants Natsu to start working for his business but Natsu doesn't want to yet. He wants to wait after high school, or college if his mom makes him go. So to distract himself, he is a player. Playing with the hearts of girls he thinks are cute. He attends fairy tail and is the biggest heart throb in the school. Girls fall for him left and right. And it helps that he is the most popular person in school.
When Lucy gets there she's not really that social. The rest of the boys take it that she won't ever talk or date them.
Natsu takes her as a challenge