The thing is, in all three scenarios, the female can romance only guys (for the sake of the question). Yhe female LIs are essentially "rivals", only instead of one, there'd be plenty. Besides, the "steal a man" cliche is also present in otoge, for obvious reasons.

For the second scenario, there's plenty of separation. And the number might be the same. This one is actually based off this game, which VNDB does class as an otome game, despite allowing you to play as a dude romancing girls.

Well, that's more of a personal opinion.

As for the example: said boy would be the male protagonist/counterpart, not an LI. You and your actual LI would just be passing by and happen to see it, as if the male and female routes were running concurrently.