No more what excuse he has, having perverted thoughts about 11 years old girls is evil !! Although he is from Japan, he is still human :D !!
The Exorcist coats are easy to explain :
1) To recognize themselves ("Hey, I'm your ally !!")
2) To bait out Akuma ("He has a coat...he is an exorcist..kill him,,)
3) To look cool (what would they wear - long brown robes of ancient librarians ??)