ok maybe not DP as you don't live together. But spend every weekend together.
He goes on your PC at home a lot, you ask him not to illegally download. He understands and agrees.
then you realise your PC is running an illegal filesharing programme and downloading something he needs (for work).
You ask him about it. He says "I couldn't ask you becuase I needed it and I knew you would say no, so I had to do it."
What do you think?