Halloween The Curse Of Michael Myers backpack

Cute Halloween backpack. Used two times total like new condition except for one minor detail, pictures show of some black “stains” on the straps of the backpack. That is the condition they were in when I purchased the bag online in new condition/packaging. I tried to clean it but it wont come off so I’m assuming it’s how the bag is made. Must go since I don’t reach for it. Please follow me for more items I will be posting daily. Thank you.