>>21874057Oh yeah, good catch. I can definitely hear the pseudo-male harmony when I'm listening out for it.
I can't tell if my brain's just making me hear whatever lines up with my interpretation but I think the harmony also stops singing along with Suisei during the very last bit, after shonen takes off the wig in the MV and starts fighting with his sister or whoever the female fan is. Or at least it's not as prominent as the other choruses.