A domain name is simply a name registered with a DNS server. The DNS server's entries can specify the IP address the domain maps to, the mail records, aliases for other domains, subdomains, etc. You can attach as many domains to a single IP as you like, and then on the server side, almost any real web server will do virtual domains. This means that each domain has its own web space, e-mail, whatever.
So, yes, you can attach your domain to her server and it will work. It will show her site, but you can get around that through virtual hosting. That is, if she has that kind of control over her server.
Another option is to setup a (free) Primary DNS for it using
http://www.granitecanyon.com/. Once setup, you can attach your domain there (read the FAQ, follow the instructions), and just leave it parked or later update the IPs to point to a server. Warning though... granitecanyon sometimes goes down, but this isn't a problem if you just want to park. Just note that sometimes, every once in awhile, if your domain points to an IP, you may not be able to get to it. It is free, afterall
