2 FOREIGN KEYS to the same PRIMARY KEY - sql

Question

I am having problem when creating FOREIGN KEY for two of my tables (Characters) and (Factions).
Let me explain the situation:
A character normally have a faction but some can have 2, so (Characters) tabel have two columns [Faction1] and [Faction2] both must be related with the (Factions) table. So I made a FOREIGN KEY (FK_Charachters(1)_Factions) with
Set Null on delete
Cascade on update
When I tried to make the FOREIGN KEY (FK_Charachters(2)_Factions) that will use the column [Faction2] instead of [Faction1] as the previous key and also make
Set Null on delete
Cascade on update
I get the error message:
"Unable to create relationship 'FK_Characters(2)_Factions'.
Introducing FOREIGN KEY constraint 'FK_Characters(2)_Factions' on table 'Characters' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints."
And of course when I set ON DELETE NO ACTION and ON UPDATE NO ACTION everything works fine but that will prevent any update for the faction.
What can I do to enforce those 2 FOREIGN KEY ?
~TIA~
(Characters) Table
USE [HDA]
GO
/****** Object: Table [dbo].[Characters] Script Date: 05/15/2014 02:38:19 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Characters](
[ID] [smallint] IDENTITY(1,1) NOT NULL,
[CODE] [nvarchar](5) NULL,
[Name] [nvarchar](50) NULL,
[NameID] [smallint] NULL,
[Tier] [tinyint] NULL,
[Grp1] [tinyint] NULL,
[Grp2] [tinyint] NULL,
[Rarity] [tinyint] NULL,
[Fac1] [tinyint] NULL,
[Fac2] [tinyint] NULL,
[Speciality] [tinyint] NULL,
[MaxLevel] [smallint] NULL,
[Power] [smallint] NULL,
[HP] [smallint] NULL,
[Speed] [tinyint] NULL,
[Attack] [nvarchar](20) NULL,
[AttackDesc] [nvarchar](10) NULL,
[PowerPerLevel] [tinyint] NULL,
[HPPerLevel] [tinyint] NULL,
[TS] [timestamp] NULL,
[CreationDate] [datetime2](7) NOT NULL,
CONSTRAINT [PK_Characters] PRIMARY KEY CLUSTERED
(
[ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
ALTER TABLE [dbo].[Characters] WITH CHECK ADD CONSTRAINT [FK_Characters_AttackDescription] FOREIGN KEY([AttackDesc])
REFERENCES [dbo].[AttackDescription] ([ID])
GO
ALTER TABLE [dbo].[Characters] CHECK CONSTRAINT [FK_Characters_AttackDescription]
GO
ALTER TABLE [dbo].[Characters] WITH CHECK ADD CONSTRAINT [FK_Characters_CharactersName] FOREIGN KEY([NameID])
REFERENCES [dbo].[CharactersName] ([ID])
ON UPDATE CASCADE
ON DELETE SET NULL
GO
ALTER TABLE [dbo].[Characters] CHECK CONSTRAINT [FK_Characters_CharactersName]
GO
ALTER TABLE [dbo].[Characters] WITH CHECK ADD CONSTRAINT [FK_Characters_Rarity] FOREIGN KEY([Rarity])
REFERENCES [dbo].[Rarity] ([ID])
ON UPDATE CASCADE
ON DELETE SET NULL
GO
ALTER TABLE [dbo].[Characters] CHECK CONSTRAINT [FK_Characters_Rarity]
GO
ALTER TABLE [dbo].[Characters] ADD CONSTRAINT [DF__Character__Creat__395884C4] DEFAULT (sysdatetime()) FOR [CreationDate]
GO
(Factions) Table
USE [HDA]
GO
/****** Object: Table [dbo].[Factions] Script Date: 05/15/2014 02:42:16 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[Factions](
[ID] [tinyint] NOT NULL,
[Color] [nvarchar](5) NOT NULL,
[Description] [ntext] NULL,
[TS] [timestamp] NULL,
[CreationDate] [datetime2](7) NOT NULL,
CONSTRAINT [PK_Factions] PRIMARY KEY CLUSTERED
(
[ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO
ALTER TABLE [dbo].[Factions] ADD CONSTRAINT [DF__Factions__Creati__4D5F7D71] DEFAULT (sysdatetime()) FOR [CreationDate]
GO