With Seamus being his adopted childer, per se, Xavier knew what was happening before anyone else. He had been watching from where he had been seated at the bar with Ben and as soon as he saw Seamus' eyes shift, he knew if he didn't intercept, this was going to get extremely messy. No one needed to see not just Jett lose his shit but also Seamus. It would be a blood bath, and the mortal wouldn't survive. He got up out of his seat and made it to Seamus' side very shortly after he had taken Luka's hand. Seamus was only a few very short steps away from frenzy here. Any tiny hint of reciprocation from Luka and he would pounce on him and sink fang into him before any of them would be able to stop him.

He seized Seamus' wrist and squeezed it tight to break his focus. "Seamus, cease," he commanded sharply with a hiss. "Control yourself." They didn't know enough about this young man to let this happen. Seamus wasn't the sort of Kindred to lose control easily, but here he was, fangs bared just slightly and even shooting Xavier a warning sneer for interrupting. This was more than just a desire to feed from a beautiful person, and just when it felt like things couldn't be more complicated, this happened.