public class Customer : IDbIdentity {
		public Customer() {
			CustomerLanguages = new HashSet<CustomerLanguage>();
		}

		#region [ IDbIdentity members ]

		public Guid Id { get; set; }

		#endregion

		public string Name { get; set; }
		public string Number { get; set; }
		public Guid? ParentId { get; set; }

		#region [ navigation ]

		public virtual ICollection<CustomerLanguage> CustomerLanguages { get; set; }

		#endregion
	}

public class CustomerLanguage : IDbIdentity {
		public CustomerLanguage() {
			CustomerLanguageDocuments = new HashSet<CustomerLanguageDocument>();
		}

		#region [ IDbIdentity members ]

		public Guid Id { get; set; }

		#endregion

		#region [ navigation ]

		public Guid CustomerId { get; set; }
		public virtual Customer Customer { get; set; }

		public virtual ICollection<CustomerLanguageDocument> CustomerLanguageDocuments { get; set; }

		#endregion
	}

public partial class PDFCEntities : DbContext {
		public PDFCEntities()
			: base("PDFCEntities") {
		}

public DbSet<Customer> Customers { get; set; }
		public DbSet<CustomerLanguage> CustomerLanguages { get; set; }

protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);

            modelBuilder.Entity<CustomerLanguageDocument>()
                .HasRequired(s => s.CustomerLanguage)
                .WithMany()
                .WillCascadeOnDelete(true);

            modelBuilder.Entity<CustomerLanguage>()
                .HasRequired(s => s.Customer)
                .WithMany()
                .WillCascadeOnDelete(true);
        }
	}