https://www.youtube.com/watch?v=fLorDVbY6KM
Fluffy had been practically vibrating in his suspended state. Spines from his body distorted the light immediately around him, obsfucating his form into a cloud (and, when the suspension was lifted, likely into a projectile volley in every direction). Though he was not able to actually escape, there was no doubt that anyone who crossed that threshold (or was in the same room with him when the suspension was lifted) would have a very bad day.
He thrashed violently within the infinite space, trying to maul anything he could reach... that was, until Belle began to sing. Her voice was, in a word, beautiful. It filled both the hospital room and the apartment where Fluffy made his lair.
It was only then that the thrashing ceased. By the end of the verse it had stopped entirely. By the end of the second verse, Noah and Mistral could hear purring.
There was, of course, the volley of tranquilizer spikes that would be unleashed when the suspension was unleashed but... for now... Fluffy was calm.