The first Invisible Man series in 10 months! After drinking a mysterious drink, the men become invisible and give in to their sexual desires. This time, they break into a ryokan and do whatever they want! Looking into the open-air bath, they discover a girl with big boobs! In the banquet hall, they discover beautiful women in yukata who are tipsy! The erection rate is sure to be the highest in the series as the fantasies explode with the feeling that they want to fuck the whole ryokan!