OniAi

After losing their parents, Akito and Akiko Himenokouji spend six years living apart with different families. When they’re finally reunited and begin sharing an apartment, Akiko’s affection for her brother quickly proves to be more than sisterly—while Akito, for his part, insists on seeing her only as family.

Any chance of a quiet two-person household disappears when three more girls move in: Anastasia Nasuhara, Arashi Nikaidou, and Ginbei Haruomi Sawatari. Each has her own interest in Akito, turning daily life into a romantic tug-of-war as competing “caretakers” vie for his attention, with plenty of bold, risqué antics along the way.