Don't be a fool, Chris. There's no future in such a student. She's solely living stuck in the past. Her whole motivation comes from a desire to kill a single man. When that man is dead, she will become a hollow husk and wither away. It also means she won't care about anything else, so she would be no fun to have around. You might say maybe she can be reformed and her high talent put to better use, but chances are she would turn only decently good, nothing more, without her obsession. After all, it was that foolish obsession that created her as a fighter.
Too bad Chris himself wants to keep facing strong opponents, so he might do it for his own amusement and benefit, disregarding the fact she won't ever be a real successor. If she happens survives him, after his death, she won't be passing the technique forward to anyone. She would just walk into the sunset and die somewhere, alone.