The antonyms for the word "pre-possess" are unimpressive, bland, unremarkable, and unappealing. When someone or something is pre-possessed, they have a particular quality that attracts people's attention and admiration. However, when they lack that quality, they become unremarkable and unimpressive. Being pre-possessed implies that an item is appealing or attractive. Therefore, when something lacks that attraction, it is unappealing and dull. In conclusion, while pre-possess is a favorable quality, its antonyms are unfavorable and indicate a lack of attractiveness or charisma.