Strictly speaking, it is not Eraser calling home (though that is what you will see if you investigate), but the Windows Root Certificate validation service, at the request of Eraser.
Eraser 6 implements its erasing methods as plugins, and will hopefully use plugins to add other features in future. Obviously, a program like Eraser needs to validate its plugins (a rogue could do very serious damage), and it uses Root Certificates, which are a core component of Windows, for this purpose. When you first use Eraser (and from time to time after that), Eraser asks Windows to check that the certificate is still valid. If, for example, security software blocks this check, Eraser will try again. The IP address you mention is owned by the certification authority Certum.