Man, it's pretty sad that this game has the corruption tag but not the romance tag.
So far, I think I remember that almost all interactions with the girls (except the teacher, lol) have a very romantic approach. In previous updates with the older sister, for example. And in this update there is clearly a lot of romance with Charelle and Nea. Especially with Nea. I found her scenes very beautiful, touching and very romantic.
With the rest of the girls we have not yet reached something as romantic as with Nea, but I get the impression that eventually they will all have their touch of romance, just like in Parental Love.