This a two part sweater: from the back it looks like two layers - one longer then the other, and from the front it looks like 당신 are wearing a strapless 상단, 맨 위로 and a sweater on 상단, 맨 위로 of it . link
사진
sweater
상단, 맨 위로
This Teen Fashion 사진 contains
카디건 and 카디 건.
There might also be
풀오버, 쓰는 타입, 슬리버, 스웨터, slipover, 스웨터, and 점퍼.