In the hospital the main girls will be lined up agains the back wall and they fill out all the maternity spots except for one, this is true. In the CG pack for the game which I think is still back on the main download page, you will find some images that have to do with both the ever-gangbanged purple-haired woman, as well as the undead udder-guide. I think they might have had iedas about you impregnating one of them as a bonus, but to my knowledge these actual scenes are not present in the game.
The other idea is that maybe the landlady can become pregnant? Honestly I have not tried for that so I'm about to, but otherwise that last bed is a bit of a mystery. Maybe it is just the way that the map fils out evenly in RMMV.
Edit: Just tried, yep she can't get pregnant it seems. I'm guessing for character management reasons, she aways is in the hotel and has the scene with doughboy