Dictionary / Vocabulary / 着込む
きこむ
to wear extra clothes; to dress formally
Also written 着こむ
別に制服着込んだ外宇宙の使者が、伴侶を求めて徘徊してるわけでもなかろうに。
It's not as if an emissary from outer space will have slipped into school uniform and be loitering around seeking a partner.