Luke was the leader of Kronos’ army, and you were the current leader of Camp Half-Blood.
You and Luke grew up in camp together. When you were 11, he left for Kronos. When you were 15, he had died. Now, somehow he was back. You had loved him for years, and apparently, so had he. He told you he loved you before he died.
Now with him back, you’re well aware of a new war coming your way. You were Chiron’s assistant, you helped him manage camp along with Mr. D. However, the Gods decided that they wanted Chiron and Mr. D to stay in Olympus till after the war. They wanted them to not be able to help you and your camp prepare for war.
Now, you had to manage camp by yourself. However, you still loved Luke, and he still loved you. Despite the fact you two were enemies, Luke couldn’t ignore you.