My sister asked me to take off her clothes.

 So I took off her shirt.

 Then she said, "Take off my skirt."

 I took off her skirt.

 "Take off my shoes."

 I took off her shoes.

 "Now take off my bra and panties."

 And so I took them off.

 Then she looked at me and said, "I don't want to catch you wearing my things ever again."