iTunes syncing friends iPod

Ok, so my friend has lent me his iPod so I can copy his music onto my iTunes and thus onto my own iPod. However, whenever I try to sync, it threatens to delete all his music. I managed to do this once before when I got a new laptop using the program senuti, however, my free trial for that ran out ages ago and I don't really want to have to pay the 18 dollars to buy it. So, my question, is there a program that is as easy to use as senuti, and does the same job, or is there another way to get his music onto my iTunes whilst keeping it on his iPod?

What you are trying to do is illegal, and consequently is blocked. We will not assist you in breaking the law, sorry.