diff --git a/migrations/V134__friends_and_foes_constraint.sql b/migrations/V134__friends_and_foes_constraint.sql
new file mode 100644
index 00000000..413a1063
--- /dev/null
+++ b/migrations/V134__friends_and_foes_constraint.sql
@@ -0,0 +1,5 @@
+DELETE FROM friends_and_foes WHERE user_id = subject_id;
+
+ALTER TABLE friends_and_foes
+ADD CONSTRAINT friends_and_foes_cannot_reference_self
+CHECK (user_id <> subject_id);