Talk:The Apartment Building/@comment-24670104-20140311203732/@comment-70.180.34.59-20150127051852

My guess is, they started fighting, maybe one of them tried to run away, the other caught up with her in the lobby and they kept fighting.

Scenario number 2, the kept aggressively discussing the issue while going up the stairs, and when they got to the lobby Penny said something really bad and Alicia started the fight or viceversa.

I guess either one of those could have happened.