看到玻璃就想照镜子？

喜欢照镜子的人，只要看到有玻璃能照到自己的样子，就会忍不住过去照一照。于是，商店的橱窗、停靠路边的汽车窗玻璃都成了假想的镜子。

A window looker refers to someone who compulsively looks into windows of buildings, stores or parked cars to check out their hair, their teeth, and everything about their appearance. People who usually behave like this are either having a strong sense of inferiority or having too much self-confidence.
Window looker指看到建筑物、商店或者停泊车辆的窗玻璃就忍不住想要照一照，检查一下自己的发型、牙齿，或者整个外表状况，我们可以称之为“照窗族”。经常有这种行为的人要不是特别缺乏自信，要不就是太自恋。

For example:

Dave, don't be such a window looker. Your hair looks the same as the last time you checked, 30 seconds ago.
戴夫，别照了。你的头发跟30秒前刚刚看过的时候一样，没啥变化。

（中国日报网英语点津 Helen）