@Thifa
Nah.... what Johannes did was understandable at the time. He was ill and knew that if he dies, the control of the family will go to his greedy relatives and not his children. The family's name is in jeopardy, his children's future are dim, and his only way to successfully buy time for Jeremy to grow up and be of age to inherit the title is to bring in Shuli.
Shuli held no political power, isn't allied to any noble factions, from a lower ranked family, and seems to be honorable which is a win-win for Johannes.
Shuli herself agreed to this terms, but I would imagine she had no idea the magnitude of the situation she was about to jump head first into, and from her POV it was a mutual business agreement. She gets to escape her controlling family and Johannes gets to buy time for Jeremy to grow up.
She even said at one point that they were both using each other, so Shuli definitely knew to an extent what Johannes' intention and expectation of her. So no, Shuli isn't 'an innocent girl' that was dragged into a mess.
Also if hypothetically Johannes didn't offer Shuli to marry him, she would've been forcefully married to a scumbag old man by her controlling mother. Shuli was dealt with shitty cards and chose what was best in the moment. Going with Johannes was the lesser evil that gave her the most freedom and agency away from her mother. No one is to blame in that situation. That's just life, shit happens bruh.