Moodwave keeps no database, so deletion is instant. Three steps, deepest first:
The Leave button on your Desk destroys your encrypted session immediately, server side and in your browser. Your tokens, profile, and library access vanish with it.
Open Spotify, go to Account, then Apps, and remove Moodwave. This revokes access at the source, independent of us, and works even if you never press Leave.
If anything remains beyond your reach, such as a hosting platform log, email pointwoebegone@gmail.com with the subject Data Deletion Request. Verified requests are completed within 30 days.