Suggested by iKnowledge The Gentleman Ghost is a powerful because it is very hard to hit him. He can become intangible at will and then appear in time to land a hit. Fortunately for Rukia her speed will make countering his attacks easy. She can match his hits as soon as he appears. I also think her ice abilities may be cold enough to affect him even when he is intangible although I am not 100% confident of that. Regardless he has no real way to damage her so eventually he will go down for the count. Rukia wins.