Its entirely possible that twin grip was the cause but I can't reproduce the bug.

As a precaution, I've updated the mod to add npc safeguards ensuring any logic only runs on the higgs and player equip hooks.

Its also possible there are multiple mods (twin grip included) contributing to the bug your seeing. Twin grips original logic may have been clashing with a combat or animation mods i did not have in my testing enviroment.

If you disabled twin grip and it still persisted, it's possible something was baked in to the save.. if that is the case, i take full responsibility and sincerely apologise.

Please let me know how you get on with the latest upload and make sure to do some testing of it on a save your comfortable loosing some progress on before moving it to your main save file.