What he could never have.
He had a lot of things, but their was one thing he wanted the most and never could have, Her love. She had a matesprite and he could never hate her to even think about being kissimisses. Besides he already had one. It was one of the many reasons they did fight, because Karkat had Jade's love and Dave was just the friend. Maybe Davesprite fucked it up for him, maybe he reminded her of him. Maybe it wasn't Davesprite's fault at all. Maybe it was his fault for not telling her, or occasionally acting like an asshole not knowing how to show her how much he cared.
All he knew was that he loved her,
And it was to late to tell her. "Dave? You ready to go we're up next." He heard her say. He turned to face her admiring how breathe taking she looked in the white dress she would be walking down the aisle to her waiting soon to be husband. "Yeah, Harley I'm ready." He says forcing a smile. She had let him wear his glass or she would have seen his eyes water. "Good,lets go." She says putting her arm in his. "Hey Harley you look amazing Karkles is lucky." She giggled and hid her blush. Before she could reply the music started and the doors opened, it was time. He began to walk he down the aisle stoping at the end of it and watching her walk to wear Karkat was waiting. He tuned out the rest of the ceremony sitting next to John and Rose.
He watched the happy newlyweds dance. He had to leave it was getting to him. He clenched his fist he wishing it was him. He stood up and looked away to the other one of the fraternal twins "Egbert I'm heading back to my apartment, tell Jade congrats for me." John knew what was wrong and nodded "see you tomorrow Dave."
He walked out the reception hall looking back to see Jade give Karkat a passionate kiss.
It was the one thing he could never have, but if she was happy with he would try to be happy for her.