Fred/Helena and whoever else is good people!
Fred practically ran back to Helena and Ginny. He did not feel comfortable leaving Helena alone with his sister. He had taught her well, and if he was alone with one of her boyfriends, before she had married Harry, he would've tortured the poor guy.
He had made it back to the pair right as Helena finished speaking. "No, call her Ginevra. She loves it," he said, smirking over at his sister. "Whatever she's said, don't let it bother you. She's just trying to be a pain. Isn't that right, Gin?" He raised his eyebrows at his sister, and then smiled at Helena, holding the bottle out for her. She looked a bit uncomfortable, and it made him nervous that she wasn't having a good time.