Protagonist Hatsuse Akira is a cheerful breast-loving perverted girl. She enjoys making models of the female body, especially breasts, and has a vast collection of breast images on her phone and PC.
Seeking the Ultimate Breasts, she moved in to an apartment by herself in order to transfer to the Imperial Girl’s School which is rumoured to be filled with lovely, pure young ladies.
The school lives up to the rumors, with many pure and lovely girls. Akira secretly declares “I will get my hands on the breasts of every girl in my class, and create a harem!”, using her new apartment as her base, she begins her breast groping battle to build her “Breast Harem”.