>>63917350I'd argue a lot of her post-Tsunderia menhera was probably still at least partially caused by her Tsunderia experience. Her manager S-Train was a genuinely malicious piece of shit who tried to keep her isolated from the rest of the company, and based on what he did to another talent years later (because of course this dude also happened to be the CEO's butt buddy so he got secretly brought back after being fired the first time just so he could ruin things even more) he probably also just straight up lied to Kana about what the other talents were saying about her and vice versa. It's really no surprise she was a mental wreck for a good while afterwards.
Here's Ember's opinion on the manager in question:
https://youtu.be/fTh2q0KQ4cI?t=7364 