Due to its large size you will need at lease three or four lights to fully illuminate it, and since cube tents are designed to give even lighting from all direction, it may not be the most flattering look on a person as it is designed to eliminate shadows, whereas on a person, you need some shadow to define their features.

For what you are looking to do, I think a collapsible background with a train such as this one.

If you are shooting indoors, then background can be leaned up against a wall, however you will need some sort of background support system such as this one if a wall isn't available.

The cube tent might work well if used outdoors on a bright sunny day however, it is designed primarily for product photography.

1. Firstly have to identify where the twist in the frame is, to do this run your fingers along the frame where the tent is dipping/sagging and find any inconsistency in the direction of the frame.
2. Now find out which was the bend is going, clockwise or anti-clockwise. If the bend is going clockwise, lift the corner push in, down and pull it back out (do the opposite if it is going in the other direction). You may find that they twist will go across to the other end of the frame, simple repeat the process again and this should put the frame back to how it is meant to be.

Please See Video Below for a Visual Demonstration