A disease that causes an obese person to see themself as a skinny person when they look in the mirror. This makes them feel the need to wear clothes that are many sizes too small, creating the mushroom top effect. Living with obexia makes the person walk around with the attitude that they are the hottest thing on the block. Also, this causes onlookers to stop and stare in disgust. Opposite of obexia would be anorexia.
The plus size woman with obexia danced in the center of the club with her undersized clothing under the impression that everyone was staring because she looked hot.