Arad is a pricolici, as much an Undead as the next vampire. He should be able to pass through the life detection barrier, but Zephyr won't. That's why he had to swallow her into the safety of his stomach.
His goal was the keyhole. If it is as large as the one in his room, he should be able to slip through.
Soon, Arad reached the keyhole. Sadly, it wasn't big enough for him to fit through. He could try, but his shoulders won't fit. Sawllowing Zephyr was a bit of a wasted effort.
With his first plan failing, it was time for the second one. Arad immediately turned his attention to the window at the end of the hallway. It led outside, into the violent storm.
This time, he'll make sure his efforts won't be wasted. He looked through the keyhole and spotted the office's window. The window was clean without a single speck of magic on it. He should be able to enter from the outside with ease.