Puberty & Boys' School!? Nakano-kun

Hajime Nakano is going to an all-boys school, yet he feels blushing and flustered around his classmates for some reason. Nakano wonders, "Am I attracted to both men and women?" But what he doesn't know is that all of his classmates are girls disguised as men... Not knowing this secret, Nakano begins high school! (Source: Kadokawa, translated)