There have been Western, English-speaking celebrities killed by fans or people at their events. Examples would be Christina Grimmie and that guy who was in the Beatles or something (I cannot remember his name. Oh right! John Lennon).
More here: https://nilefm.com/celebrity/a…ebrities-murdered-by-fans. The article was written in 2019. These are from all places not just the West.
It lists:
Dimebag Darrell - killed in 2004 by Nathan Gale, an "extreme fan".
John Lennon - killed in 1980 by Mark David Chapman, a former Beatles fan who "turned against Lennon due to a religious conversion and Lennon's highly publicized 1966 remark about the Beatles being "more popular than Jesus."[14] . He had been considering killing other famous public figures too. [Can be considered a fan]
Suzanne Tamim - killed 2008 by Mohsen al-Sukkari, a hitman hired by Egyptian businessman Hisham Talaat Mostafa. Some sources say he was a romantic affair partner, others say his motive is unknown. [Most likely NOT KILLED BY A FAN]
Selena - killed 1995 by Yolanda Saldívar, "Saldívar had been the president of Selena's fan club and the manager of her boutiques, but she lost both positions a short time before the murder, when the singer's family discovered that she had been embezzling money from both organizations." It was "over financial differences". [Technically a fan, but pretty unusual circumstance]
Zikra - killed 2003. Most sources say by her husband, but Wikipedia says the murderer was not identified. [Most likely NOT KILLED BY A FAN]
Christina Grimmie - killed 2016 by Kevin James Loibl, said to be obsessed and infatuated with the singer.
Gianni Versace - killed 1997 by Andrew Cunnan. Cunnan had killed 4 other men prior but was said to be obsessed with the designer. [Can be considered a fan]
2pac - killed 1996, murderer never identified. [Probably NOT killed by a fan]
Notorious B.I.G. - killed 1997, murderer never found. [Probably NOT killed by a fan]
(All additional information from the article or Wikipedia)
So removing the ones with unidentified or non-fan murderers that is just 5 famous people who were killed by fans: Dimebag Darrell, Lennon, Selena, Grimmie, Versace.
I just googled to see if any J-pop idols were killed by fans. I found 1, Mayu Tomita (killed 2004). I am not sure if there are others or others documented only in Japanese.
I also googled "korean celebrities killed by fans" "korean actors killed by fans" "korean singers killed by fans". But could not find any murders of famous Korean people. It is possible there are some that are not documented or are only documented in the Korean language.
Why do you think no one has been killed by a fan yet? I know about the glue story and going to a fansign to slap someone story but those did not have murderous intent.
Edit: By the way I have read just the preface and ending of Perfect Blue, and I thought for sure there must be some real case that the book is based on. But I don't think there is.
Nothing comes up for "japanese actors killed by fans" or "japanese celebrities killed by fans" either. Or maybe there are cases not documented on the internet, or only documented in Japanese