Lies That She's Sick And Can Only Be Cured In a Perverted Way

He recently got a new shipment of Kryptonite and started working on a new way to trick Kara. He crushed the Kryptonite into tiny amounts and used them for various things. He used them as seasonings for food for Kara, in soap for her, in her shampoo. He used tiny amounts in various products in her life, knowing that she'd use it.

His help was for it to make her sick. Since it's such a small amount of Kryptonite, it'd be easy for him to use a device to undo the effects. In other words, he can easily make her sick and make the symptoms go away whenever he wants. He can even lie about why she's sick and why the symptoms are leaving.

He can tell her that it's her body having trouble adapting to Earth and that to get better, she needs to do a variety of lewd things. Things she'll get so used to doing that once the symptoms are completely gone, she'd keep doing them.