What is the difference between light BDSM sessions and BDSM sessions?
Generally, the BDSM session is up to the discussion with the therapist. You are welcome to share your desires with her upfront.
Light BDSM includes light bondage, eyes covering and movement restriction. The therapist will treat you dominantly.
The therapist can also use some BDSMtoys if you like during the BDSM session.