体态轻盈的家燕，长得一对又尖又长的翅膀，尾巴像一把剪刀，身披一件蓝黑色的外衣，额和喉部都是棕色的，下体雪白，在校园的上空飞来飞去。
O O O O O B-Thing I-Thing O O O B-Metric I-Metric O O O O O B-Thing I-Thing O B-Thing I-Thing O B-Metric I-Metric B-Thing I-Thing O B-Thing O B-Metric I-Metric O O O O B-Thing I-Thing O B-Thing O B-Thing I-Thing O O O O O O B-Thing I-Thing O O O O B-Location I-Location O B-Location I-Location O O O O O