Based on the manga by Komiya Sanae and Nonomura Hideki.

Dr. Narutaki, a genius who is trying to preserve true Japanese men, not the losers they are today, needs semen from 100 specimens. The problem is these 100 specimens wouldn't give it to him voluntarily, so he comes up with a plan. He gets Marin, a sexy girl from an all girl school, and puts her into a special costume that transforms to a mans desire and won't come off until she gets all 100 semen samples. However, Southpole One, a sexaroid created by the doctor's assistant, is interfering by exhausting and taking the men's semen first, making it a race.

"For the bright future of Japan, I shall take your semen!"