Once a character has been created, the Delete button on the sheet does not appear to function, and they cannot be removed from the list of created characters. Their sheet continues to function normally, but unwanted sheets end up clogging the list.
When opening a character sheet owned by a different account while actively logged in, the sheet appears as if it's editable, and changes can be made to the data on the sheet. Upon refreshing, the sheet returns to its original state, so it doesn't appear that this actually updates the database, making it relatively harmless, but it is a bit of an odd difference compared to viewing while not logged in, which disables all of the fields.