Melissa Hayes is a mindcaster. She has the ability to hear the thoughts of those around her. She is also able to manipulate people mentally by adding or removing thoughts. In addition, she has the ability to completely incapacitate a person by making them forget how to take care of themselves, including moving their muscles, eating, and talking. The other midnighters refer to this as a mind rip and are disgusted by Melissa for her ability to do this.
She typically describes her mind reading as a sense of taste, because in certain behaviors, moods or thoughts are associated with certain bitter or sweet tastes. She can use her power during regular time but she much prefers to use it during the blue time because the subject is unaware and cannot stop her. Upon meeting Madeleine, she further hones in on her abilities to make them stronger and control them better.
Melissa is in a romantic relationship with Rex with whom she has been friends since she was 8 years old. Throughout the book Rex refers to her as "Cowgirl" in reference to how they met.
Melissa is often referred to as rude and many of her friends, especially the midnighters (with the exception of Rex) do not trust her. The midnighters tolerate her because of her useful abilities.
