While the attack on Diana had pulled strongly on the feelings Adam would always have for her, it had also plucked at those he had for Cassie, if in a different way. It went without saying that he wanted to hunt down the person, the monster that had done such things to Diana. He would have felt similarly if anyone in the Circle suffered such a savage attack. Sure, with Diana it was more personal and those feelings were a little quicker to rise because of how close they were. It didn't change that he would want to hurt anyone who hurt the Circle.
But if it had been Cassie that he found out there in the grass? Adam didn't want to even entertain the possibility because of the hot swell of emotion it caused, and the way that emotion flared his magic to life.
He had never been the vengeful sort, or the type to think bad things about other people -- other than Jake after he had stolen from his father, but even then it had been within moderation -- but Adam found such thoughts close to his mind. The presence of his magic was a comfort, even if he fleetingly worried about lashing out without thinking. It wasn't something he had ever truly worried about before, but then, this place had him thinking about things he had never needed to think of.
Adam knocked on the main door and called out, "Cassie, it's me," before he let himself in, knowing they were all likely on high alert in the wake of Diana's attack and not wanting to startle Cassie. Perhaps one of the others would have been worried about her reacting impulsively with her magic if she were startled but that was a thought Adam never worried about with Cassie. Even in the wake of everything, even with her having choked him before. Perhaps that kind of trust was crazy, but some might say the way he felt about her was crazy too.
Would he still feel that though, being here, with another Cassie around? It was something Adam had felt some concern over but a concern that had since dissipated after the way he felt Cassie's presence the night they found Diana. Of course, that then brought a different question to mind. How was it that he could feel a similar draw to two separate people, even if they were versions of the same person? As if he really needed such complication to worry about, when he was still trying to figure out what was potentially wrong with his magic. Which was the reason he wanted to come see Cassie in the first place. Well, most of the reason. He also simply needed to see her. After all, where he was from they were still together, and he had no idea what had transpired during Casino Night while he had been inside the school, waiting for Cassie to return.