Alter her biology

You woke up the next morning to her radio playing some music. You looked down and saw she was lying over you at an angle looking unbelievably cute.

You immediately went hard, which seemed to wake her.

"morning" she said, "god I'm so tired"

"Do you want me to help"

"Please" she groaned.

You concentrated and then both of you immediately got out of bed. Neither of you felt tired any longer.

"Wow" she said. She jumped off the bed and went to her closet to get dressed. While she was picking what to wear you simply opened your case and threw on a white shirt and some jeans.

"Do you know what a white shirt is perfect for?" She asked you.

"No?"

"It's perfect for tits." She tuned around and pulled on a tight white top. She seemed to have chosen not to wear a bra underneath, so her nipples were rather obvious through the top. What was even more obvious, was how hard they were.

"Oi" she said, "just because they're hard doesn't mean I'm horny." It was as if she read your mind

"Well, time to change that" you snickered, as you changed the biology of women everywhere.

"Wait what"

"You heard me. Now, women's nipples get hard quicker and easier than ever before, and when they do, they will cause you to become slightly horny."

"Unfair" Rebecca said, folding her arms. The slight brush of her nipples unprotected against fabric caused them to go hard, and she blushed. "let me change something about all guys then"

"Go ahead, tell me what "