Ziall-Love Don't Cost A Thing

Zayn was the leader of a gang. Sean was the leader of a rival gang. They hated eachother, the bad blood between them run deep. Niall, Sean's cousin was innocent. He knew nothing about the world Sean was involved in, until he came face to face with Zayn. They should have stayed away from eachother, but they couldn't. Niall got to know Zayn and they fell inlove, nobody wanted them together but they loved eachother. What happens when that love is revealed? What happens when Niall becomes Zayn's biggest weakness?