A shoujo anime about a girl who exorcise demons with the help of 3 guys About 2 years ago, I watched a shoujo anime about a girl who went to an all-girl school. I think her name sounded something like angle.

She had the power to exorcise demons and did so with the help of a few handsome men. One of them had red hair, another had green hair, and the other one had some connection with the school. As for the characters, I don't remember a lot. The male with red hair was energetic and did not warm up to the main character at first. The second male, as I recall, had green hair and met the protagonist under a table (?). He was very "happy-go-lucky", and was warm and friendly to the protagonist.
I'm not sure if this matches entirely your description but since you mentioned "handsome men", "red hair", "all-girl school", "exorcising"... I thought of one thing:

Neo-Angelique Abyss

-Protagonist is a girl coming from an all-girl school
-There's a guy with red hair named Rayne
-Another guy with green hair named Nyx (dark green)
-Then another guy with green hair named JD (light green)
-Then some elf guy (I think) with silver hair  

You could try here to see if it really is the anime you're looking for.

EDIT: Now that I think about it, this may not be actually the anime you're looking for.  Because, whoops, I mentioned four guys. I don't remember much the anime, anyway.