In case anyone was wondering how Tetsu was doing
https://twitter.com/zigzo_official/status/1066607322720436224
More Tetsu, just in case
https://twitter.com/zigzo_official/status/1023542324175896576
https://twitter.com/zigzo_official/status/1023416716401860609
https://twitter.com/zigzo_official/status/1022515839902380033
In the 25th Anniversary pamphlet, when asked about Tetsu, Mana said "he's a rocker". That's why Tetsu left, and he's been doing what he wants to do ever since. Being a rocker.
I know Juka wasn't mentioned, yet his name does come up. He also went on to continue to perform until he decided to leave because he didn't want to deal with the music industry in Japan. He has said this a number of times on Instagram. As to why he left Moi dix Mois, I really think goth wasn't his thing. Poor boy couldn't handle wearing black clothing all the time. If you look at his work before and after, he was more into glam visual kei. I still think he was hoping Moi dix Mois was going to be Malice Mizer II.
https://www.instagram.com/p/BqfP-c4Fq6P/
As for Klaha, he didn't leave. Afterwards he had some success, but I had read (I wish I had citations) he had some fear of performing live. Although in a way, he went from small stage to Budokon, which would be intimidating for almost anyone, along with the fandom. He was doing rather well after that but chose not to continue. Since he decided to not be public, anyone speculating beyond what has been written is just that, speculation. I hope his life has been good.
I just felt like writing something.
As for the Japanese fandom, it's pretty much "Yay Malice Mizer!" "Yay Mana! Yay Közi! Yay Yu~ki!" Over all it's not that crazy. Közi has a really good following because he's very active. Mana has very devoted fans. And there are people who still love Yu~ki even though he hasn't been around much. And then there is the Gackt camp, who follow him no matter what he says or does. It is what it is. Overall the Malice Mizer 25th Anniversary shows were seen as very positive.
My personal advise if one comes across someone who is still hanging on to stuff like this that may or may not have happened long ago is to just say "手放す".