Teppen no Himawari Mangaてっぺんのひまわり
Ryuhei Ohno has finally graduated middle school leaving behind the pains of unrequited love and the trials of adolescence. He is determined to make a fresh start in high school. On the first day of class, he meets Kunihisa Imaizumi. Kunihisa has joined the school not knowing that 90% of the student body is gay! And to put it mildly, he is a bit wary of his fellow classmates. Ryuhei appoints himself as Kunihisa’s protector, but he soon finds himself being drawn to his firm gaze… Description taken from DMP..