Lena wanted to go back to her father's room but chose to avoid it knowing that Julius hadn't left yet. Her troublesome Uncle whom she'd rather not see chose to remain as stubborn as herself. Wanting to be by his brother's side even if that meant his niece refused to occupy the same space with him so soon after everything that took place. She'd eventually have to be in the same space with him. Just not when she was uncertain whether that would involve pulling a gun on him again or not.
The princess instead found space away from everyone on a different floor. Having created enough chaos in Leo's room, she didn't want to go back there yet. Hence, the sixth floor would have to do for now. She would take some time to breathe and figure out what to do next.