affable
easy-going, friendly
alacrity
promptness in response; cheerful readiness; eargerness
amiable
friendly; agreeable; good-natured
benign
kind and gentle
sanguine
cheerfully confident; optimistic
belligerent
eager to fight; hostile or aggressive
byzantine
extremely complicated or devious
cantankerous1
ill-tempered and quarrelsome; disagreeable
contentious
quarrelsome
deleterious
having a harmful effect
exacerbate
to increase the severity, violence, or bitterness of; aggravate
flippant
disrespectfully humorous or casual
insolent
insulting in manner or speech
nefarious
flagrantly wicked; vicious
pernicious
extremely or irrevocably harmful; deadly
rancorous
marked by bitter, deep-seated ill-will
repugnant
arousing disgust or aversion; offensive or repulsive
tawdry
gaudy and cheap