McDermott believes Pogrebnyak, who is due a work permit hearing this week, will fit in well with his side as they bid to stay in the top flight next term.
The Reading boss told the Daily Mirror: "The owner had a chat with Pavel about six weeks ago, towards the end of last season. I met him, too.
"He took a long time. He showed us a lot of respect and we're delighted to get him. It shows where we are going as a club.
"He's a great transfer for us. An excellent player.
"But what more drew me to him was that he is a good person. A good character. He works really hard for the team and fits into what all of my players have shown over the last season.
"We kept talking over those six weeks. We needed him to know how important it was to us to get him. That was made very, very clear."