public IHttpActionResult Follow(int id)
 {
     if (_userComicService.IsFollowing(id, UserId))
     {
         _userComicService.Delete(id, UserId);
     }
     else
     {
         var seriesId = _comicService.GetSeriesIdForComicId(id);
         if (!_userSeries.IsFollowing(seriesId, UserId))
         {
             _userSeries.Add(seriesId, UserId);
         }
         _userComicService.Add(id, UserId);
     }
     return(Ok());
 }