There's no well - known real - world incident specifically named as something that happened at Nakatomi Plaza in 1988. However, in the movie 'Die Hard' which is set in Nakatomi Plaza, there are a lot of fictional events. Maybe it's a misnomer or a very specific local reference that's not widely known.
In a Christmas story taking place in Plaza House Square, the square could be transformed into a winter wonderland. There might be ice skating rinks set up, and people of all ages are having a great time. The local church might organize a special Christmas mass in the square, with the beautiful sound of bells ringing in the background, and everyone coming together to celebrate the joy of Christmas.