Skyrim Mod:Mod File Format/RELA

RELA records contain information on Relationships between 2 NPC_ or an NPC_ and the player.

C	SubRecord	Name	Type/Size	Info
+	EDID	editorId	zstring	Editor id
+	DATA	Data	struct[16]
		Parent NPC	formid	Parent/child here does not necessarily mean biological parent/child; it's just a generic way of describing two connected items.
		Child NPC	formid
		Rank	uint16	Relationship Level. The value stored in the game data is unsigned integer ranging from 0 to 8 (although 7 is the highest value being used so far). However, this is converted into a value ranging from -4 to 4, which is the value returned by GetRelationshipRank; negative values imply dislike/hatred whereas positive values are for friendship. The meaning assigned to each value in the CK is (the first number is the raw value in the game data; the second number is the GetRelationshipRank value): 0 - Lover (4) 1 - Ally (3) 2 - Confidant (2) 3 - Friend (1) 4 - Acquaintance (0) 5 - Rival (-1) 6 - Foe (-2) 7 - Enemy (-3) 8 - Archnemesis (-4)
		Flag	uint16	The only bit set in this flag is the highest bit: 0x8000 - Secret
		Association Type	formid	Formid to a ASTP record, which provides additional information about the association between the two people. Can be empty, in which case no additional information is available.