This story originally appeared in volume 53 of the Japanese alternative comics anthology AX. For my money, it is the best story in the collection — a sweet, sentimental tale of young love told in a charming visual style.
NOTES:
The word 水色 (mizuiro, meaning “light blue”) is made up of the characters for water and color, so the title of the story could also be translated as “Love is the Color of Water.”