The phrase "uncaring others bad egg" typically refers to someone who is unfeeling or indifferent towards others, and who has a negative or unpleasant character. There are many synonyms that can describe this type of person, including callous, heartless, cold, cruel, unkind, mean, and self-centered. Other possible options include thoughtless, indifferent, unfeeling, unsympathetic, and inconsiderate. Regardless of the specific word used, the central idea behind all of these synonyms is that the person in question lacks empathy, compassion, or concern for others, and may behave in ways that are hurtful, selfish, or insensitive.