Steve might not notice the dancing pink light hovering near his head - or if he did, it wouldn't change anything. The image was relayed back to Nanoha all the same - and she took to the sky, zeroing in on the boy-turned-monster's location in the city.

"There you are... I've found you."

Nanoha had promised Miku and Luis she wouldn't act rashly, but... she had faith in her own monster-fighting skills. If she could capture Steve non-lethally before he hurt anyone else? So much the better.