code: public function afterDelete()
      {
          // after complete owner delete delete tags links
          if (!empty($this->_tagsForDelete)) {
              $relation = $this->owner->getRelation('tagsList', false);
              if ($relation instanceof ActiveQuery) {
                  /** @var ActiveRecord $class */
                  $class = $relation->modelClass;
                  // decrease counters
                  $class::updateAllCounters(['count' => -1], ['in', $class::primaryKey(), $this->_tagsForDelete]);
                  // delete links
                  $this->owner->getDb()
                      ->createCommand()
                      ->delete($relation->via->from[0], [key($relation->via->link) => $this->owner->getPrimaryKey()])
                      ->execute();
              }
              $this->_tagsForDelete = [];
          }
      }
docs: After delete event