Lost Blue Hour

Three days ago, we stopped being "best friends"... It was four years ago. They were paired up in gym class and hit it off right then and there, and began to spend every day together. One day, Yukiya's feelings suddenly overflowed after seeing Aoba's kind expression on his face, and he confessed to him. He gets a yes and they decide to go out, but he is still clumsy and shy, sometimes to the point of crying. However, he wants to go beyond kissing Aoba, whom he loves, and tries to get a classmate who is rumored to be gay to teach him how to do it......? (Source: Kaiohsha, translated) Note: Includes one extra chapter.