The PUA's words were clearly effective, leaving Otome Yumeko utterly baffled as the affection and infatuation in her eyes became increasingly intense. The hands that had been clasping Haruka's arm tightened around him, almost as if she wished to merge them into one.
"Of course I won't leave you, Haruka... We'll always be together, what's mine is yours, including my life. My future life will be built upon you... Even now, not being able to be by your side every moment is for our future, I've wronged you during this time...."
Love makes a person impulsive, emotion overriding reason, and right now, Otome Yumeko was in such a state, and even more intense than being passionately in love.
If Haruka Yuzan told her to die, she would not hesitate to abandon everything and then... pull Haruka with her in death.
You can't understand it with normal reasoning, but... these are the expressions of their love, a love crazed to the point of terror.