Draco Malfoy loved Hermione since he first saw her. When he first saw her with her muggle parents, standing at the train station he was shocked that someone so beautiful could have come from muggles.
He tried to convince himself these feelings were not true, so he harassed her and such, but despite the pain when she slapped him in third year, he couldn't help but smile when noone was looking. He scorned himself later for this, there was no way he could have feelings for a filthy mudblood!
Through the years his feelings for her grew, but his ability to shield them also increased. However after Harry stole his wand at Malfoy Manor and he was aloud to retire in his room, his tears flowed freely. "She would never love me! Not after all this! I should of known it earlier! How could I have done all this to her! I've lost my chance!" he screamed in his head, for want of not being heard.
Hours after the Battle of Hogwarts when he was walking around the castle all alone, he saw Hermionie and Ron together kissing and whispering sweet nothings to each other, completely oblivious to him. His throat caught."What does she see in him?" he asked himself. He wanted to go up to Hermione and tell her everything. But she looked so... happy. So he decided to leave her there.
A few years later he met Astoria. She was beautiful and smart as heck. She reminded him so much of her. He didn't quite fall in love with her, but he liked her enough. When he asked her to marry him he almost called her Hermione, but caught himself just in time.
When he saw her at Kings Cross and the way Scorpio looked at Hermione's daughter he knew what was happening. Maybe this Malfoy would have the courage to talk to a Granger, well, the daughter of a Granger anyhow.