From vnsharring:

Cheena is a bright girl who works for a living at Hibari Chou, one of the richest towns in Japan. Her mother passed away from an illness and now she lives alone with her father with a huge debt from his business failure. Cheena is worried about the expensive school fees, but when she talks to her teacher about it, she is reassured that an anonymous supporter has been paying all her fees! Who could it be?