Stanley says "Be comfortable is my motto"
Stanley also says "She'll go. Period. PS Tuesday"
Blanche said "The touch of your hands insults them"
Eunice says "You can't beat on a woman an' then call 'er back!"
One of Stanley actions are "Stanley stalks fiercely through the portieres into the bed- room. He crosses to the small white radio and snatches it off the table. With a shouted oath, he tosses the instrument out the window"
Another act of Stanley is "Hiyuh Blanche (He grins at her)"
Stanley is definitely a round character because he is complex. You never know what he will do or stick his nose into. At one moment you think he's all for being with Stella and the next minute he's flirting with Blanche. Then he goes from hitting Stella to begging her to stay with him. You couldn't just determine Stanley by one word because he is many. He is a brute, clever, sneaky, a liar and many more which makes him a round character.
From all the information and quotes that I've gathered above, I would say that Stanley is a thief. I say this because he took the life out of Blanche by constantly agitating her to the point that she snaps and gives in. Which also leads her to going into a mental institution. He has literally stolen her life from her when all she wanted to do was relive her younger days when she was in love. He's a thief to Mitch because he stole his love; Stanley never had the right to tell Mitch those things and snoop through everyone to find them. Mitch had feelings for Blanche and possibly would've married her and they could've worked those things out themselves. He's a thief to Stella because he brainwashes her and makes her think that he loves her when he really doesn't. He flirts with Blanche behind her back and makes dirty comments all the time. He also uses Stella only when he needs her and takes her sister away from her just because he didn't feel the same way about her. A