[@White Feather] 

Neither it's a school, for one Sasha and Itsuko are just trying to win a breast measuring contest really, see which ever one is better at what they do by using Luci, if it was any other male character then I think they would've either have the two fight to the near death or chosen one instead of staying in the middle. 

And if this was a mental institute then we wouldn't have people like Izumi here, plus a harem would require a number of girls you have 2 confirmed as harem.