Tsukiatte yo! Satsuki-chan

Overview

When she was a little girl, Satsuki made a promise to her friend Tetsu that if he became strong and able to protect her during the 10-15 years he would be living and studying in China, she would date him. Well, 10 years have passed, and Satsuki has grown (oh boy, has she) and is very strong at karate in her own right, and Tetsu is coming back. And he is strong, although he hides it at first. Thing is, can she compete with all of the other girls who are now interested in Tetsu?

Source: AniList