Sting 'accidentally' mated with Lucy. What will he do about this?

Lucy, left alone in Tenroujima, was bitten by a vampire: Zeref. She found out that she's betrayed, and Zeref promised to train her to make up for his deed. Later, they found an ice mage also bitten by an unknown vampire in the island. He trained both Lucy and the ice mage. When they come back to Fairy Tail, they were forgotten. Will the vampires have their revenge? [ON HOLD]