What building was located at the southwest corner of the forum and what two purposes did it serve for pompeians?

The Basilica of Pompeii

Explanation:

In the southeast corner of the Pompeii Forum stood a building of Basilica. It was the oldest basilica of the time and represented one of the nicer buildings in the city and the Forum itself.  Also one of the most important buildings in ancient Rome.

Inside it was divided into three naves naves with two rows of brick columns. Also the decoration was well done where the judges sat in wooden chairs and discussed acute situations.    

It's  purposes were:

dramatic irony is your answer