public static async void StartDeleteMasterPlayerExample(Action<PlayFabError> callback)
{
    var task = await PlayFabAdminAPI.DeleteMasterPlayerAccountAsync(new DeleteMasterPlayerAccountRequest()
    {
        PlayFabId = PlayFabId
    });

    if(task.Error != null)
    {
        callback(task.Error);
    }

    var jobReceiptId = task.Result.JobReceiptId;
    var AffectedTitleList = task.Result.TitleIds; 
    foreach (var title in AffectedTitleList)
    {
        Console.WriteLine(string.Format("Delete Player - Title Affected: {0}", title));
    }

}

//Make sure we are 100% sure we want to do this.
if ( confirm successful ) {
   //create a variable to store a list of titles the player has already been removed from.
   listOfTitlesRemovedFrom
   //Hang on to the receipts from successful deletes.
   listOfReceipts
   foreach(title in <all my titles>){

       //You only need to remove the Master Player once per namespace, so check that you have not
       //already performed this action in the namespace, or you will get an error that
       //the player is already queued for deletion.
       if(title not in listOfTitlesRemovedFrom){
           foreach(pfid in PlayFabIdList){

              //Note: you should do some error handling around this API call.
              response = title.DeleteMasterPlayerAccount(pfid)
              foreach(titleId in response.titleids){
                listOfTitlesRemoved.add(titleId)
              }
              listOfReceipts.add(response.jobreceiptid)
           }
       }
   }

   //Save listOfReceipts somewhere as proof of deletion.

}

{ 
    "Entity": { 
        "Id": "<The ID of the target entity>", 
        "Type": "<either ‘title_player_account’, ‘master_player_account’, or ‘character’>" 
    }, 
    "Objects": [ 
        { 
            "ObjectName": "<Name of object to delete>", 
            "DeleteObject": true 
        } 
    ] 
}