Add additional, model-imposed failsafe for (main) character deletion.

drakul/users/models.py

@@ -123,5 +123,12 @@ class Character(models.Model):
     def clean(self):
         self.name = self.name.capitalize()
 
+    def delete(self, *args, **kwargs):
+        if self.user.main == self:
+            # Sanity check: this is already checked by the profile and admin forms which allow character deletion, but
+            # we check it again to avoid unintentionally cascading the delete to the entire user.
+            raise ValidationError("Can't delete user's main character.")
+        return super().delete(*args, **kwargs)
+
     def __str__(self):
         return self.name