How to point domain to different host sub folder?

Question

Hi,

I have a host and domain on asphostportal.com, and I have a subdomain like : sub.domain.com. Now my friend has another domain like frienddomain.com and he point to my host.

How can I point his domain to my subfolder sub. Everytime he open frienddomain.com it will show my site on sub.mydomain.com. Currently he show mine mydomain.com sites.

Is this possible?