Most Helpful Girl
Haha. Like tomatoes.
Well, sometimes we do it for men, for women, or for ourselves. Obviously, there's a connection between you and makeup on this woman. Think about all of the ads we see. We're brought up to think makeup=pretty, sexy, feminine. Guys love women who look more feminine. Blush makes you look happier and healthier, it was made to look like the post-orgasm rush of blood that women get. The redder the lips, the heathier the woman(so science says). Longer eyelashes are associated with females too. All of these are little triggers in the male brain. It goes back to nature :)
I think she likes you, wants to impress you, or just get more attention from you.
The other alternative is that, some days, we just want to look pretty. Just because.