Hermione and Percy wrote to each other a lot, but they were rarely actually around each other. When they were around each other, though, it was special.
When Hermione was invited to spend a week at the Weasleys, during which Bill was getting married, she went. She had been reluctant to leave, but she didn't want to miss this opportunity.
At the wedding, she found herself dancing with Percy. A few years ago she had enjoyed dancing with Neville at the Yule ball, but there was something about dancing with Percy that just felt a bit more special.
Hermione had been having a wonderful time, and Percy seemed to be to, until a Patronus showed up and warned them that the ministry of magic had been taken over by Voldemort, and the minister was dead.
Hermione let go of Percy, and apparated, during which Percy grabbed her hand. Once in front of Sirius's house, Percy practically yanked her inside.
"I'm so sorry," Percy said. "I should have seen this coming."
"You're a Ministry spy for the Order," Hermione pointed out, "not a Seer."
"Thanks," he said. "That makes me feel a little better. Anyway, you're safe so I'm going to go back to my family." With that, he was out the door.
Percy had taken a full week off to help out with the wedding, and spend time with Hermione during her visit. The idea that Percy should have predicted this disaster seemed absurd, yet she could not help but wonder that maybe if she hadn't come he wouldn't have taken as much time off, and maybe then he would have noticed.
Hermione knew she had to tell everyone the bad news. She turned to see Jane, Neville, Mrs. Longbottom, and Sirius, all starring at her. Even Crookshanks, Trevor, and Ingrid were starring at all. The humans each had a bowl of cake and ice cream. As Crookshanks walked up to Hermione, to greet her, Hermione realized that she had forgot about Neville's birthday.