For just 8€ extra per month (if you have a monthly or annual subscription), you can add up to 4 additional users to your subscription.
You can stop this option at any time, and it will have no impact on your basic package.
All that's left is that the people registered for this option will no longer have access to the service at the end of the paid period.
Note that this option is only available on WEB subscriptions, not on those taken out via the application.