NFDM-405 A man forced to be a guinea pig for a science girl's forced ejaculation

All members of the Chemistry Department at Freedom Girls' Academy are currently researching the "mechanism of male ejaculation". The sperm, which is the research material, needs to be "an object fired from an erect ball", but since it is an all-girls school, the absolute number of men is small, and "securing sperm" is the most important issue. . I don't have time to present my research at a student conference, so I'm in the middle of forcibly collecting sperm by bringing a man into the club room with that kind of hand.