How to say “pen and paper roleplay game”?
桌上角色扮演，or in jargon among players: 跑团。

P.S. It seems that other answerers don't know the term 跑团游戏, which amazes me.

Edit:

The etymology of 『跑团』is unknown to me, but I guess it's because "a group of people playing (running) in the virtual world".