Just a heads up, despite the popular myth, it's totally fine to clean cast iron with soap. The seasoning is a polymer (plastic) that is bound to the pan. The soap destroys grease, but the polymerized stuff isn't effected. You don't need to every time if you don't feel like it, because heat should clean things fairly well, but don't be scared to do it if it's dirty.
Useless context: the soap thing used to be true when soap had lye. But now, like overcooking pork chops and washing chicken, it’s outdated advice from our grandparents.