Why would my ex go out of his way to see me?

My ex owes me a huge amount of money. I had saved a number ages ago from which he phoned me. So randomly I phoned it and then thought better and put it down before anyone picked up. I didnt think much of it till a few seconds later when he called me back. He asked if it was okay for him to come around I say yes. He waits till a stupid hour to come around twelve forty midnight. I hadn't seen him since last may so had to give him directions as this was my first flat. I was hoping he came to see me because he wanted to. But he rudely deleted the number from my phone saying he could get into huge trouble if they find out he is getting private calls . I think its because his girlfriend works there. Then he started to delete his old phone numbers. He tried to get close if you know what I mean and I told him I cant because his got a girlfriend. He told me I was giving him a guilty concience. I dont beliveve he wanted to see me for anymore than hes own selfish reasons.