You are the first one to get into Triangle, then who am I?

Male lead story, the protagonist is a male version of Chu Hua in another world)
[Includes some of the old group's (mainly anime) plots, developed according to the timeline]
In order to see his childhood friend Toyokawa Sho (male), Sankaku Hatsuka (male) went to see the performance of the boy band crychic, but found himself traveling to a parallel world.
Brother Xiang, how did you become a woman?!
How did a boy band become a girl band!?
How come there is a female version of me! ?
(I am an author who is motivated by interest. I wanted to write this after seeing Nan Xiang. Please don’t call me a swindler. QWQ)