Although Toshio Matsumoto acknowledges that an interest in the Oedipus story is what gives this film its shape, he also says the primary motivation for making it was to document Tokyo's emerging gay subculture. And so the plot is constantly interspersed with documentary – including interviews with the actors about the motivation of their characters. Those interviews are sometimes rather uncomfortable to watch – calling to mind Foucault's idea that the demand to disclose your feelings is in its own way oppressive. The questions are often accusatory (what about getting married? don't you like women as well?) and the subjects answer or evade them with as much dignity as they can muster.
It's often quite a fun film – Matsumoto is keen to exploit every cinematic trick he can think of, so there's slapstick routines (mostly absurd catfights), wild psychedelic parties, free love, drugs and (rather violent) student politics. The film employs a cut-up technique, short scenes scrambled together, and sometimes revisited. The effect is to present a kaleidoscope of gay life, building up a sense of a particular place and culture, rather than sticking to a certain character or narrative.
That said, the director's use of the Oedipus story provides a (rather artificial) backbone to the film. By having to follow in Oedipus's footsteps, the protagonist is given a dark past and a doomed future – which casts a pall over the fun and games. The film seems to suggest that these characters are running away from broken families, and are all destined for early deaths. Matsumoto is too fascinated by the counterculture he is filming to condemn it, but the logic of the story he is telling means the film cannot be celebratory either.
Why Oedipus is so interesting to Matsumoto is unclear. Perhaps the transgressive nature of the tragedy serves to underscore the transgressiveness of queer sexuality, particularly in the 1960s, and particularly in Japan. To transgress means to offend propriety, and live with the shame of not being able to conform. The film ends with the protagonist being stared at by a circle of random people on the street, the outrage of the incest melding with the outrage of a nonconformist lifestyle. There's no way around that sort of Greek tragedy, even if one hopes that the subculture the film explores continues to grow and thrive.