Obnoxing
A person who's so annoying they make you want to punch them in the face. Basically the same as being a pain in the ass.
My neighbor's kid kept screaming at me every day. He was an obnoxing person.
My cousin's friend kept texting me and asking me out. He was obnoxing.
My mom's friend kept talking to me and ignoring my mom. She was obnoxing.