title: Laravel belongsToMany with multiple tables
body: <p>I have a table called creative and two another tables called title_set and image_set.
  They relative with each other by the creative_set table.</p>
  <p>So basically, I have:</p>
  <pre><code>creative:
      id
      title
  
  title_set:
      id
      title
      
  image_set:
      id
      image
  </code></pre>
  <p>And the relation table:</p>
  <pre><code>creative_set:
      creative_id
      set_id
  </code></pre>
  <p>Now, I create the model and the relations:</p>
  <p>Creative Model:</p>
  <pre><code>public function imageSets()
  {
      return $this-&gt;belongsToMany('App\Models\ImageSet', 'creative_set', 'creative_id', 'set_id');
  }
  
  
  public function titleSets()
  {
      return $this-&gt;belongsToMany('App\Models\TitleSet', 'creative_set', 'creative_id', 'set_id');
  }
  
  public function creativeSets()
  {
      return $this-&gt;hasMany('App\Models\CreativeSet', 'creative_id');
  }
  </code></pre>
  <p>I create a function to remove the relationship:</p>
  <pre><code>public function deleteRelations()
  {
      $this-&gt;titleSets()-&gt;delete();
      $this-&gt;imageSets()-&gt;delete();
      $this-&gt;creativeSets()-&gt;delete();
  }
  </code></pre>
  <p>Now I create two creative A (Title Creative 01) with one relation model (Title Set 01) and B (Image Creative 01) with one relation model (Image Set 01).</p>
  <p>When I update the creative A, I will call deleteRelations function and recreate new items.</p>
  <p>The issue is, it not only remove the titleSets of the creative A but remove the imageSets of the creative B also. Why do we have the results for $this-&gt;imageSets()?</p>
  <p>Any mistakes here?</p>