As Bruce looked at her, he realised that he recognised her from the network. He liked keeping an eye on Percy, making sure he wasn't getting into too much trouble. Most of the time he was just messing around and joking with his friends and not really getting into that much mischief and if he was Bruce was normally too busy or distracted with his own projects to notice. But he did notice the key players, Merry, Ruby, Magnus, Percy, Krissy and Dawn. Now that he got a good look at her, even though she wasn't looking him in the eye, he knew he recognised her, this was Ruby, Percy's girlfriend.
"I don't think he's in. Must be out at the aquarium or something," Knowing Percy, if he wasn't doing something related to water, it was something for his friends. "It's Ruby, right? I'm Bruce. It's good to meet you, even if it's just an awkward little run in." He shrugged. He didn't hold anything against Ruby for avoiding eye contact, it might have been something related to anxiety, social nuances or something. Or it could have been something related to her powers.
"I've got a spare key, do you want to come inside and we can wait for him to get back?" he asked gently, he didn't know that much about Ruby other than what Percy had told him, which was generally how amazing she was, and that she had been adopted by a family of bears. He was hoping to learn a little more about her, but at the same time he didn't want to potentially spook her or anything. There was something about the way she avoided her gaze, she seemed tense. Bruce recognised tension well.