Rainbow Under the Sun

Bronze award at The 5th International MANGA Award Guntur did not come from a wealthy family. In order to pay for his school fees, he had to work part-time helping his father in a building construction project. As a result, Guntur had to stay in class several times. But Guntur didn't mind his situation. After all, the money he earns from working can still be saved for Nisa, his younger sister who is smarter. But... is it fair for Guntur to sacrifice his future for his sister? (Source: Goodreads, translated)