Within 15 sec of your going online with that machine, your ports will be scanned. And without even the latest SP and additional security updates or a software firewall protecting it, the nasties will be on board.
Without all its updates and add-on security software (FW in particular), XP is a Zombie bot magnet.
. Besides which, he would be able to tell you had used the comp, which apparently you aren't allowed to do except under narrow limits. So then you may not get to use it at all, ever...
.bh.