Java → Kotlin

android studioで開発中のアプリをConvert Java File to Kotlin Fileで変換したところうまく動かなくなりました。 
エラーが発生しているのはRetrofitで使うデータクラスの部分です。 
Parcelableはプラグインを使って作成しました。

public class Word implements Parcelable {
//一部抜粋
    @Expose
    private Integer id;
    @Expose
    private String keyword;
    @Expose
    private Integer type;
    @Expose
    private Integer level;
    @Expose
    private String summary;
    @Expose
    private String description;
    @Expose
    private boolean nonfiction;
    @Expose
    private boolean fiction;


//Getter, Setterは省略

    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeValue(this.id);
        dest.writeString(this.keyword);
        dest.writeValue(this.type);
        dest.writeValue(this.level);
        dest.writeString(this.summary);
        dest.writeString(this.description);
        dest.writeByte(this.nonfiction ? (byte) 1 : (byte) 0);
        dest.writeByte(this.fiction ? (byte) 1 : (byte) 0);
    }

    public Word() {
    }

    protected Word(Parcel in) {
        this.id = (Integer) in.readValue(Integer.class.getClassLoader());
        this.keyword = in.readString();
        this.type = (Integer) in.readValue(Integer.class.getClassLoader());
        this.level = (Integer) in.readValue(Integer.class.getClassLoader());
        this.summary = in.readString();
        this.description = in.readString();
        this.nonfiction = in.readByte() != 0;
        this.fiction = in.readByte() != 0;
    }

    public static final Creator<Word> CREATOR = new Creator<Word>() {
        @Override
        public Word createFromParcel(Parcel source) {
            return new Word(source);
        }

        @Override
        public Word[] newArray(int size) {
            return new Word[size];
        }
    };
}

これをConvert Java File to Kotlin Fileで変換すると赤波線が出ます。 
上記のコードをKotlinで記述するにはどうすればいいのか教えてください。 
変換後のコードは下記。

//Kotlin
class Word : Parcelable {
    @Expose
    var id: Int? = null
    @Expose
    var keyword: String? = null
    @Expose
    var type: Int? = null
    @Expose
    var level: Int? = null
    @Expose
    var summary: String? = null
    @Expose
    var description: String? = null
    @Expose
    var isNonfiction: Boolean = false
    @Expose
    var isFiction: Boolean = false

    override fun describeContents(): Int {
        return 0
    }

    override fun writeToParcel(dest: Parcel, flags: Int) {
        dest.writeValue(this.id)
        dest.writeString(this.keyword)
        dest.writeValue(this.type)
        dest.writeValue(this.level)
        dest.writeString(this.summary)
        dest.writeString(this.description)
        dest.writeByte(if (this.isNonfiction) 1.toByte() else 0.toByte())
        dest.writeByte(if (this.isFiction) 1.toByte() else 0.toByte())
    }

    constructor() {}

    protected constructor(`in`: Parcel) {
        this.id = `in`.readValue(Int::class.java.classLoader) as Int
        this.keyword = `in`.readString()
        this.type = `in`.readValue(Int::class.java.classLoader) as Int
        this.level = `in`.readValue(Int::class.java.classLoader) as Int
        this.summary = `in`.readString()
        this.description = `in`.readString() 
        this.isNonfiction = `in`.readByte().toInt() != 0
        this.isFiction = `in`.readByte().toInt() != 0
    }
    companion object {

        @JvmField
        val CREATOR: Parcelable.Creator<Word> = object : Parcelable.Creator<Word> {
            override fun createFromParcel(source: Parcel): Word {
                return Word(source)
            }
            override fun newArray(size: Int): Array<Word?> {
                return arrayOfNulls(size)
            }
        }
    }
}

エラーメッセージ 
Caused by: android.os.BadParcelableException: Parcelable protocol requires a Parcelable.Creator object called CREATOR on class com.example.myapplication.Word
意味が分からなかったらすみません。