App crashes on CoreData deletion...how to code this correctly?

I have 2 core data entity's set up with a many to one and one to many relationship between them (Show -> Season one to many / Season -> Show many to one). I have the class for Show manually created with the code below. However, when I delete a show or season (if only one), it is crashing the app saying 'Fatal error: Unexpectedly found nil while unwrapping an Optional value' for the following code in the manual class, which was setup to create the relationship between the two entities. I have the app set up to use a for loop to delete all seasons of a show prior to deleting the show as well, which causes the same error obviously because there are no seasons left. How do I fix this so that it deletes all seasons without an error?

**Shows+CoreDataProperties.swift (manual class for Show Entity)
**

@NSManaged public var season: Set<Seasons>?

    public var seasons: [Seasons]{
            let setOfSeasons = season
            return setOfSeasons!.sorted{
                $0.id > $1.id
            }
        }

Deletion code within view

    // DELETE SHOW
    public func deleteShow(show: Shows){
        deleteSeasonsinShow(show: show)
        viewContext.delete(show)
        do{
            try viewContext.save()
        } catch{
            print(error)
        }
    }
    
    // DELETE SEASONS WITHIN SHOW PRIOR TO DELETING SHOW
    public func deleteSeasonsinShow(show: Shows){
        
        for season in show.seasons {
            viewContext.delete(season)
            do{
                try viewContext.save()
            } catch{
                print(error)
            }
        }
    }

Use a guard statement in the computed property to avoid having to use forced unwrapping

public var seasons: [Seasons] {
    guard let season else { return [] }
    return season.sorted {
        $0.id > $1.id
    }
}

First of all your naming is confusing with regard to singular/plural. Entities are supposed to be named in singular form and a to-many relationship is supposed to be named in plural form.

If Show is created manually anyway, declare the set as non-optional Set by removing the question mark and unchecking Optional in the model

@NSManaged public var seasons : Set<Season>

And actually you don't need the conversion to Array. The set can be enumerated like an array.

If you really need an optional add a computed property which unwraps the optional safely

var unwrappedSeasons : Set<Season> {
    return seasons ?? Set<Season>()
}

And - unrelated - do not save the context multiple times in a loop. Call it once after the loop.

public func deleteSeasonsinShow(show: Shows){
    
    for season in show.seasons {
        viewContext.delete(season)
    }
    do {
        try viewContext.save()
    } catch{
        print(error)
    }
}