If you're trying to find a way to describe someone who is unpleasant and offensive, the word "obnoxious" may come to mind. However, if you're looking for a more nuanced or specific way to convey this type of behavior, there are plenty of synonyms at your disposal. For example, you might use terms like "noxious," "offensive," or "disagreeable" to describe someone's behavior or attitude. Other possible synonyms include "repugnant," "disgusting," "unappealing," "revolting," or "disconcerting." Depending on the context, you may want to choose a synonym that emphasizes a particular aspect of someone's behavior, such as their arrogance, rudeness, or insensitivity.