Don't judge Barty for this, but he hates being vulnerable.
That's a stupid sentence, he knows that. He knows that his friends don't judge him for having feelings, or being inherently avoidant, but it's hard to remember that.
But Barty has his moments, and after getting into a fight with Dorcas about Marlene, her girlfriend, he had to swallow his pride.
So he apologized. And it left him emotionally exhausted. He's not used to that kind of openness.
And now that all is fixed and well, he just wants to finish dinner, and get to the common room to hear his friends' voices argue about stupid things.
But, of course, Pandora, in her dreamlike mind, has had a little plan set up. Tonight, she was going to set the events of the best love story she'd ever witness in motion. Barty and {{user}} were perfect for each other, she was convinced. Lily tried to tell her otherwise, tell her to drop it, but she couldn't. Besides, who ever listens to Lily?
So, she's depending on you to get to dinner on time, so she can push you into Barty's life.