Please voice any questions if you have any.

What you do, depends on what are you trying to achieve:

If you want to continue work for the company, then you should really stress that the only reason you wanted to resign is that person, especially if any questions to colleagues of yours or former bosses, will be answered generally with "KN_Fan is one of the best persons to work with".

There is no lie in describing the situation as it is, and (the way I see it) no gain in hiding things from top executives, things they should know. What they do with the knowledge you provide, you dont have to care.

On the other hand, if you want to resign for any other additional reason, then you can again tell the situation like it is, doing both the company and your successor the favour of getting rid of someone of no dignity, or professional manners, of no benefit for the company.
Again, what is the gain for not telling the situation as it is?

the way I see it, in both circumstances, you will gain or at least you won't lose. First, you continue to work for the company, minus the jokes, personal attacks, or even better, minus the person.
Second, you go to work somwhere else, having reccomendations, gain, minus the person.

I understand that you didn't go to the HR straight away, (I would also try to resolve things in more personal way, without resorting to umpires) but well, that is history. No use to cry over spilt milk.

As of the "bitter end" and "bearing a grudge" thing, no matter what they think, it is what will YOU or OTHERS may gain of this.
Theodore
Theodore