Bikyaku Seido Kaichou Ai.

Yoshizawa Atsushi has a strong fetish for pantyhose. He instantly falls in love with student council president Ninomiya Ai's black tights and joins the council so that he could be closer to her. Unexpectedly, Ai treats Atsushi horribly, which makes him regret joining the council. However, one day he finally manages to avenge himself as he sneaks into the president's office and successfully finds her weakness. He then blackmails her and turns her into his sex slave.