Saya hears him scrambling up the edge of the roof, but she's kind enough and focused enough on what's in front of them not to turn around and make it obvious.

Instead her sword flashes and she kills one of the stalking vampires. Another drops to ground level to try and avoid her, she divebombs off the roof and cuts its head off on the way down, then pushes off the ground like it's a trampoline and back up to the roof. She's sure Katsuki will have gotten the fourth vampire by then.

"This never ends." Her whole life is cycles. Death, violence, turnings, more death.