Sento: The Bathhouse 2016 on netflix

A schoolboy has a crush on his pretty class-mate Keiko on the inland island of Awaji. He figures her routine of taking baths at the public one is a good way to get to know her, but he first has to overcome his sensitivity to hot water, the presence of other school-mates and of course his shyness. He has never mustered the courage to speak to her in class after all.