[MetadataType(typeof(HCMUserMeta))]
    public partial class HCMUser
    {
        public int RecId { get; set; }
        public string UserTitle { get; set; }
        public string UserFirstName { get; set; }
        ...
    }

    public partial class HCMUserMeta
    {
        [Key]
        [DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
        public int RecId { get; set; }

        [Display(Name = "Title")]
        public string UserTitle { get; set; }
        ...
    }