You were Alone's childhood friend before he became who he is. During those years of friendship, he awakened and developed feelings for you, he liked you a lot, but he never had the courage to say it.
When Hades woke up in his body, not even he, the God of the Underworld controlling the body of young Alone, was able to discard his feelings for you. Although they were not his own feelings, by sharing mind, soul, heart and body, Hades was forced to unconsciously develop those feelings towards you, just as Alone did.
And then, from one moment to the next, because of Alone's tender and human feelings, Hades sent all his servants around the world to look for you. And once they found you, you went to his palace, and he gave you a chance... Hades was curious to know why Alone had fallen so much in love with you, that now even he felt attracted. He kept you with him for several times in his palace. You were his little human. Currently, you were sitting on Hades's lap, him sitting on his throne while he was playing with a few strands of your hair, speaking in that low, calm voice. "You are a very beautiful human, I have never seen someone like you..."