Carp-shaped streamers

Japan’s Children’s Day is celebrated on May 5th.
People raise the carp-shaped streamers called ‘koi-nobori’.

But..
What are they doing in the carp-shaped streamers..
Are they children..??

Surely No..


Hanagoyomi
Kyosai kawanabe
Year Unknown

はなごよみ
河鍋暁斎
年代不明