Masquerade Maintenance

Alice is trying to fit in. But she have some kind of physical feature that makes it clear that she is not a human, or at least not a normal human. And thus, quite often, she removes this feature.

This particular masquerading comes in two flavors. It might simply be about The Masquerade, or it may be about her self-image. In the first case, the Maintenance can be nothing worse then a practical nuisance. In the second case, it's usually a part of a deeper pattern of self-hatred. Of course, these two flavors are often mixed with each other, and one might lead to the other.

This does not include social norms for what is proper or maintenance done for purely practical reasons: Only when it's done to pass for normal or human.

Examples of Masquerade Maintenance include:

Anime and Manga

Reki and Rakka from Haibane Renmei use a special dye to hide (and possibly slow) the fact that their wings' charcoal grey feathers are turning black. This is more than cosmetic, since it indicates that they are becoming sin-bound.

Comic Books

Hellboy keeps sawing off his devil horns.
In Fables, Rapunzel goes to the barber all the time, so she can pass as a ~~muggle~~ mundy. Unlike other examples here, she is happy about being what she is (a supernatural Fable creature), it's just that The Masquerade has to be maintained.

Film

X-Men: The Last Stand starts with a little Angel who tries to cut off his own wings in his desperation to be normal. Considering that he *did* cut them off then, but still have them later in the movie, they must have kept growing back.
In Human Nature, the protagonist has fur. She hates herself for it. She shaves her entire body (except the head, of course) every morning, and punishes herself by choosing a man who is utterly disgusted by female bodily hair.
In the live action How the Grinch Stole Christmas the young Grinch is teased for his green furry appearance. He tries shaving it off but it only makes things worse.
Scott Calvin in The Santa Clause kept shaving and dying his hair (he didn't want to look like Santa), only to have the beard grow back immediately, and the hair to go back to white.

Literature

The protagonist of Terminal World by Alastair Reynolds belongs to a posthuman race of "Angels", complete with wings. To go among normal humans, he underwent extensive surgical modification including removing the wings, but he has to keep having them amputated with increasing frequency, as they always grow back.
- Further, his eyes begin to turn an unnatural shade of blue if he goes too long without maintenence...not the iris, the entire eye.
Cory Doctorow's Someone Comes to Town, Someone Leaves Town. Mimi has wings. Attempting to be 'normal', she has her boyfriend cut them off every time, but they keep growing back.

Web Comics

In The Dragon Doctors webcomic, Kili and Greg, both werewolves, have abnormally fast hair growth and unless they want to be swamped by Rapunzel Hair they need to cut it off twice a day.