Fred/Helena and whoever else is good people!
Fred had just nodded at Helena and was debating to get her butterbeer or if she would just prefer water when his sister came up to them. This couldn't be good. Fred visibly rolled his eyes at Ginny's words. "Helena, this is my sister, Ginevra," he said, gritting his teeth. He had a feeling that Ginny's main goal was to embarass him, or see if he could embarass himself.
He turned to Helena and said, "Im going to go get you a butterbeer," and smiled at her. As he passed Ginny, he whispered casually, "Behave yourself, yeah?" He quickly made his way to the bar to get two butterbeers, planning to return as quickly as he could to rescue Helena.