Log Horizon

From the introduction: For those who don't know, Log Horizon is a light novel/web novel series in Japan that has been adapted into an anime currently on its second season. The series itself is about a group of people who have gotten sucked into an MMORPG called Elder Tale. This new world is a mix of their laws of physics and the game's and the people who were sucked in are now their characters. In a sense, this means that PCs in this RPG are playing people who are playing video game characters.