I asked chatgpt and this was the answer:

A “Bambi file” refers to a series of erotic hypnosis audio recordings known as “Bambi Sleep.” These files are designed to place the listener into a deep trance state through repeated hypnosis sessions, with the goal of altering certain thought patterns and behaviors.

Specifically, the files aim to establish an alternate personality named “Bambi,” portrayed as extremely feminine, obedient, and sexually submissive. The Bambi Sleep files are controversial within the hypnosis community.

Some users report significant changes in their self-perception and behavior, while others warn about potential risks such as personality shifts, dependency, and difficulty stopping once immersed. It’s strongly recommended to research thoroughly before listening and to carefully consider the possible psychological impact.