Many animals have bits that flush with blood and become redder when they are ready to mate, so it makes sense that 'redness' can be a turn on. However, IMHO, when you redden lips using makeup, it's fake, and doesn't turn me on. I'm much more attracted by a natural redness, (e. g. blushing and swollen/parted lips) than fake colours from cosmetics. If you want to redden your lips, just give them a bit of a massage! From my point of view, more makeup = higher maintenance - something to avoid. Therefore, the less makeup a girl is wearing, the more attractive she is to me. It tells me she has a strong mind i. e. she hasn't been conditioned by society to believe that she isn't beautiful without it, and/or she an environmentalist, ie. she has an understanding of how the cosmetic industry is such a drain on finite planetary resources and is such a creator of trash and pollution that she'd rather vote with her feet and not use them.
Depending on the shade of red, absolutely. It's one of the probably top five things a woman can do to me more sexy. Generally men prefer brighter reds with more yellow than the darker reds with more blue that are generally preferred by women.