So there was this one time where Ouma invited them to a boys sleepover.
When they got there, there were three people missing.
Ouma claimed "Those straight f*cks ar boring!" And said nothing else, though he also said Gonta didn't need to be here.
They all ended up drunk and f*cking, which is what Ouma wanted.
So basically Amami, Kiyo, Kiibo, and Ouma were f*cking.
No one knows how they got Kiibo to participate.
Saihara was there as well, but he doesn't drink, so he would never participate.