Regulus had been waffling anxiously about how and when to tell Sirius about Gemma for, oh, four months, the exact length of their relationship. It was awkward because Sirius had been on that blind date with her, and awkward because Sirius, good-hearted as he was, had a penchant for teasing, and Regulus was sensitive about this. Still, he wanted his brother to know, because this was serious to him...
Which didn't prevent his nerves from being through the roof when he arrived at their ancestral home at long last. He stepped through the Floo and glanced around, noting any small differences since he'd last visited Grimmauld Place.
"Hi, Sirius," Regulus said. "It's good to see you."