This is not meant to tow a car, this is meant to pull a small trailer and there are certain precautions when you tow a vehicle, the towing vehicle should be heavier than the vehicle in tow otherwise you get into a situation where the trailer wags the tractor and you end up upside down on the road.
Your vitz has no towing hooks - the little eye toyota provide is to pull the car onto a trailer bed and tie it down with that too. Using a rope on the rear suspension linkages etc is a 100% guarantee to bend them out of shape.
Its basic common sense that you dont tow a vehicle without proper safety checks and procedure (check your owner's manual - OH, its a JDM its either lost, missing or in japanese)