The Nine Mile Walk. 1
What does "for the pleasure of rubbing it in" mean in sentence below.

I HAD MADE an ass of myself in a speech I had given at the Good Government Association dinner, and Nicky Welt had cornered me at breakfast at the Blue Moon, where we both ate occasionally, for the pleasure of rubbing it in.

I tried to google that, but answers was definitely wrong.

Question

The Nine Mile Walk. 1
What does "for the pleasure of rubbing it in" mean in sentence below.

I HAD MADE an ass of myself in a speech I had given at the Good Government Association dinner, and Nicky Welt had cornered me at breakfast at the Blue Moon, where we both ate occasionally, for the pleasure of rubbing it in.

I tried to google that, but answers was definitely wrong.

Answer

rubbing it in = to take something bad and make it worse.  Like when someone makes a mistake and you laugh at them you are RUBBING IT IN.

Answer

His friend Nicky took pleasure in reminding him how he made an ass of himself in which case it is translated as 'rubbing it in' like having a laugh at him.

(That's just my interpretation, hope it helps.)