A human girl (self-proclaimed succubus) is the only one in the monster girl class, experiencing an interspecies yuri school life. The harpy Hayate faces another period of egg blockage and secretly hopes that her admired Sakura will help her lay eggs. During physical education class, a volleyball-like game called "Sepak Takraw" is played, where the use of tails, tentacles, and wings is allowed for mixed races, leading to fierce battles that showcase the individuality of each species. Afterward, in the gym storage room, two beings with different bodies and feelings come into contact. The fresh struggles of the monster girls and their dazzling swimsuits shine in Volume 4!