Normally, it is not as WhoisGuard is a separate service; although, the system will suggest that you renew WhoisGuard during the domain renewal.
Also, you can set auto-renewal for the domain and WhoisGuard.
To do that, log into your account, go to Domain List, click on the Manage button next to your domain and find the Status&Validity section. There, you will be able to toggle the button to enable the Auto-renew feature for WhoisGuard.
You can also refer to this article for the detailed instructions.
That's it!
If you have any questions, feel free to contact our Support Team.