LARPer       
noun [ C ] (also larper) uk/ˈlɑː.pər/ us/ˈlɑːr.pɚ/
 真人角色扮演游戏玩家(live-action role player的缩写)
abbreviation for live-action role player: a person who takes part in games in which players dress as particular characters and act out their parts in the game
  While on campus earlier this week, I learned of the existence of LARPers, or Live Action Role Players. 
A larper is someone who enjoys dressing up as their favourite fantasy character for role-play. 真人游戏玩家就是喜欢在角色扮演游戏中打扮成自己最喜欢的幻想角色的人。 
 - More examples
 - LARPers - and those who find their pastime laughable - meet in this fun documentary.
 - A "larper" (from "Live Action Role Playing") is someone who re-enacts fantasy scenarios by dressing up and taking a character role.
 - Apparently these folks don't just like Dungeons and Dragons, they carry foam swords around, pretend to fight other LARPers and take the whole thing semi-seriously.