An OVA bundled with the eighth volume of the Seitokai Series Spinoff novel. 

Sugisaki Ken, through diligence and academic excellence, had successfully entered the paradise that is the Hekiyou Private Academy's Student Council. There, he boldly embarks on his plan to create his personal harem with the 4 girls who are the other council members, namely: The incredibly youthful president Sakurano Kurimu; The cool and kindly yet super-sadistic secretary Akaba Chizuru; Tomboyish and hot-blooded vice-president Shiina Minatsu; and The ephemerally beautiful yet complicated treasurer Shiina Mafuyu. While every day since then has been non-stop fun, Graduation Day now looms near. Could this spell the end of their carefree days? <br><br>
(Source: translated and adapted from official site by Cranston) 

Spin-off series for the Seitokai light novel series.

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