My sister watches me

In America we have these things called bathroom locks. They're great, you should try them sometime.

Put soap on the tiles so when she sneaks in she slips and falls maybe shell learn her leason

Get a video camera, place it in a hidden location in the bathroom and start recording. It will record your sister coming into the room and watching you. Then, show the video to your parents.

I don't know what os more ridiculous, this story or your username.

Regardless, you stated you do lock your doors, so she must be pretty crafty in opening locks. Perhaps put the lock on the door facing upward at the top of the door she cannot reach. She is also twelve, as you stated, so you and her must be living with your parents, correct? Inform you parents so they can tell her it is wrong, and if she continues to do so or continues to try, tell your parents again so she can get punished and learn it is not a good thing to do.

watch her when she showers. make it even.

just kidding don't do that.
uhh, i don't know man.
I still don't get how she's getting in there if you lock the door?

She'll crawl into your bed to fondle your cock and balls while you are sleeping, I bet. Just tell her that since you are too old to rub her pussy, she is too young to jerk you off.

Just take all of her bobby pins. Doesn't matter how high her lock picking skill is with no bobby pins. (Someone please get the reference.)

Sound like a Lannister kind of family you have there.

Sounds like a burgeoning pervert... You don't say how old you are, I hoping that you are at least of age otherwise, if younger than her, her reasons could be even darker. Are you catching my drift?

If you are a minor and your parents won't take this seriously, perhaps another authority figure would?

Anyway, can you put a lock in the door?

maybe she wants u to fuck her how old is she

Maybe your dick is so small,she can`t decide if you`re a boy or girl? :-)

If she is going through puberty, they being curious about the male anatomy is normal. But as others have said before, if you don't want her there, lock the damn door!

Poop in the shower... she'll be gone.

Jerk off for her!

I suggest proving it to your parents. Is there anywhere where you may be able to store an electronic device which can record? Preferably something small, like a phone. That way there is a reduced chance of her catching onto the potential plan.

I need help

ignore her. she'll get bored looking at you eventually.

Stick something sharp in her eye! Just kidding, but she is probably deserving of a black eye.

Do your parents know she does this bullshit? How old is she? Are you her brother or sister?