
Janine is the head of the Admissions Department at SJS. She works in the office with Sister Mary Constance, who assists her. However, Mary Constance is often times unnecessary, as Janine can easily handle the office all by herself-- or all by herselves, to be more accurate.
Janine Sinclair-- known as Gemini to many of the students-- is an extremely powerful mutant. She has the ability to duplicate herself many times over. Each "twin," as she calls them, operates independently and there seems to be no "original" Gemini twin. Each Gemini twin speaks of itself as "we," which can confuse people at times. The twins themselves are quite accustomed to their unique abilities.
Gemini and her twins act as recruiters for SJS, with twins operating all over the world, searching out new students. There seems to be no "duration" to her ability to duplicate. The twins can exist independently for months with no ill effects. When two of her twins recombine, they do not have perfect recall of the events that they experienced when they were individuals. The memories become slightly hazy.
Gemini has another power, one which makes her potentially extremely dangerous. She, and any of her twins, can touch another individual and copy some of their thoughts, memories, and abilities-- including super powers. If she copies the powers of another super-human, she also acquires the knowledge and experiences necessary to use them. However, once a twin has copied the powers of another person, that twin temporarily loses the ability to duplicate itself. After the twins recombine, the copied powers are lost, but memories of the experience remain.

It was this power that led to the greatest tragedy of her life.
Gemini was educated at the Bloodvine Academy, and it was there she learned to harness her abilities. However, like all Bloodvine students, she was taught that a pursuit of excellence must include a quest to increase one's own power. It was because of the teaching of Lady Bloodvine and the other faculty at Bloodvine Academy that Gemini attempted to duplicate the powers of an extremely dangerous villain she encountered while on patrol.
The results were unexpected. Though the twin was able to copy the villain's powers, she also copied his dangerous, unstable mind. The twin became irrational, aggressive, and possibly homicidal. When the twin returned to the Bloodvine Academy, Gemini refused to recombine with her, fearing what the results might be. The twin became hostile, demanding to be reabsorbed into Gemini. After a frantic standoff, the twin attacked her sisters. Gemini and her twins were forced to kill the rogue twin to prevent her from recombining with Gemini.
Gemini left the Bloodvine Academy soon after. She is deeply resentful that she was forced to destroy one of her twins, and she blames not only herself, but what she now views as the twisted teachings of the Bloodvine Academy. When she learned about Saint Joe's, she became one of the school's strongest advocates. Gemini would rather that no young person ever turn to the Bloodvine Academy if they do not have to.
Strangely, because of her role in the administration, she continues to have contact with the Bloodvine Academy. She tries to keep a civil tongue, but she has made her true feelings known on more than one occasion.
Spoiler: Update from the conclusion of BVA's Invasion storyline.