Me cago en tu madre!
You are "rude".
Call them a blood clot
Asinine is an insult. It begins with the letter a.
There are many websites and blogs that have lists of insults including Buzz Feed, which features Shakespearean insults to Wikipedia, which has a list of ethnic insults.
lul (dick) sukkel (stupid) idioot (idiot)
insults starting with the letter L
Rude people are an excellent source of insults. Also Chavs