Frankly, I would just as soon as Shussei dump Aoi if they're going to be in a long-distance relationship. She has already proven that she has no resistance to other men making physical advances on her and she would most likely end up eventually succumbing to some sleazebag, like Shuu's brother or Leon, and at the very least becoming some other guys sex friend. Love is not always enough to keep someone faithful, endure the loneliness and resist tempation.