Male sexual function testing center. Abbreviated as Sex Exam—

It is an institution operated in cooperation with local governments and major adult entertainment groups to examine whether men are in a condition to properly procreate.

Ando, the protagonist, came to this "Sex Exam" for the first time in two years, but fortunately, the attendants are the number one popular "Azusa" and number two "Eri," and he receives dreamlike and attentive examinations (sexual services) from the two.

As a result, his relationship with the two becomes even deeper...