Never forget(Dragneel brothers Fairytail fanfic)

Zeref and Natsu story A secret buried deep within the heart of Fairytail will soon be revealed. Strange events start to occur when a young man appears to on Tenrou Island. Who is this man? What's his purpose? Why is he here? However,the most haunting question of all is....How does he know the young dragon slayer, Nats...