I wouldn't use nair. A lot of people I know have had bad reaction, and that's just on legs etc. The chemicals are very strong, some people's skin does not work well with them.
Have you tried waxing? Like going to a professinal? It may seem embarrassing, but more women have facial hair than you'd know, and most waxers offer female facial waxing. That or threading? You can get little devices for threading yourself, or just twist up some thread. It works kinda the same as waxing, pulling the hairs out from the root ... I know a few girls who use it on their faces
