Doesn't really matter about consensual, who started what or who stalked whom and what the age of consent is or whether they are both 'adults'. A college takes on a certain level or responsibility for the students that enroll - not quite in loco parentis but fairly close, and that responsibility includes ensuring that their employees are not behaving inappropriately with their students. And most employees of universities sign contracts that specifically proscribe inappropriate behaviors with students. Coaches and teachers specifically are in positions of authority over their students and players that make any relationship between them unbalanced regardless of consent or initiator. It is the same type of situation that is codified in medical ethics relative to doctor/patient relationships - there can be no 'consent' because there is no way of determining if it is given freely or is being coerced.
And it is exactly the same reason that their are laws regarding statutory rape - society has determined that up until a certain age a person is not mature enough so 'consent' is not possible.
You may bridle at the use of the term 'victim' but there is an assumption that someone who attains the level of head coach has a level of maturity whatever his or her age that they will recognize that their position is one that carries the responsibility to act appropriately in this situation and will recognize that 'consent' has no meaning and is no defense for not acting appropriately.
And I agree with others - adultery is a fact of life and it appears that professed religious belief has little effect on whether it occurs or not, only on whether or not one is able to seek forgiveness from an all forgiving god. I don't condemn the huge portion of married people who have committed adultery, but I do condemn those who have whether or not they are married abused positions of responsibility or power to engage in inappropriate relationships with those placed in their care or under their authority.