When Master is doing those things to torture his mouse, like when she's bound, sometimes gagged, blindfolded and struggling to hear for clues to what might happen next, she flies away. She feels her body soar, and she is transported to a different realm of reality. As the pain increases she goes further away, into a soundless world. She is vulnerable and knows there is nothing she can do to stop it. If she does speak it comes out like a word salad, everything mixed up and nothing makes sense. Trust keeps her in that world for as long as Master wishes her to remain.
The power and responsibility Master must feel when he knows he can do anything he wants. She is reduced to just being a living puppet and he can pull the strings anyway he wishes.
Meanwhile she's flying high above her physical body, lost in a realm that is peaceful, shocks of pain reverberate, yanno like turbulence but nothing more a little quiver. A reflex, or maybe a twitch is noted but otherwise she is gone.
Then she feels herself falling, sometimes it's almost a gliding sensation, slowly coming down to earth like a feather. Other times it feels like she's plummeting which can only be described as falling from a plane without a parachute. She falls and lands hard. Suddenly she is alert and aware of her surroundings, often with a scream of searing pain. If Master wishes he can allow her to drift back to the stars but sometimes he wants her to feel what he is doing. He wants her to feel the pain in it's fullness, he will drive it to be more and more intense. She will soon buckle under the strain of it all and he knows it. She is breaking apart. He stops just before that moment. Her punishment is over and she thanks her Master.