Ml forgiving her and not dragging it out is the right choice. The only thing she did wrong was choosing death to get ml to move on. He fell in love with her characters and kept forcing her to transform. There is no reason she should need to reveal she has a crazy transforming device to him. They were only boss and employee relationship, not even friends. Why should she trust he wont do anything bad to her to get it.
The show started out nice and fun but then the plot became a complete mess. Every character started making stupid decisions one after another. Most of the characters were just selfish and their decisions ended up harming themselves or people they love. I also find the ml having random future things and his knowledge of so many different subjects completely bullshit.