If we assume that no exclusive event can be triggered (which is reasonable, given that sel has said and reaffirmed that it will be possible to have a single PT that hits all events), that means that none of the other choices can trigger an event. And I'm pretty sure that that means that none of them will trigger a sex scene, because:
1. Sex scenes are replayable in the gallery as events with "neutral" variables, which means that a conditional H-scene hidden inside a mandatory event is not easily worked into his current system,
and
2. Sel likes punishing people who play LiL for the porn value, so blueballing everyone who requested an unrealistic 3some would be entirely on-brand. This idea is supported by the current update, where Yumi reacts to a 3some suggestion exactly like you would expect her to and we will likely see more of the same from the others. For example, we'll probably see Rin say something like "lol no way, a 3some with my former crush would destroy my relationship with Otoha" (which is exactly what you'd expect her to say).
My guess is the Chinami option will come back in the form of some abusive dialogue forks but not anything substantial.