Hito toshite Tsukiaetara

Asakura's virginity is aggravated daily by his burgeoning desire to have a girlfriend. Meanwhile, he manages to become close to Tsukishiro-san, a beautiful woman he has adored since he first glimpsed her at work. They start meeting up frequently, and just when it seems they might be about to have a physical relationship, she informs him of her (a)sexual orientation!?

(Source: Kodansha, translated)