Otome Games

Mystic Messenger!
I liked quite a few of the Shall We Date ones.
I also was a Voltage fan, but after they moved stuff to a single app, I lost most of my stuff, so I'm not biased.   There were a few there I like,d but I haven't touched them since, so I forgot the names. D:

I don't think I ever played any of the Shall We Date ones.  I have some of the old Voltage ones on older phones that were nice because I prefer buying the full route rather than dealing with the daily tickets.  
Mystic Messenger was set up nicely for that I think.  You could play without spending money AND once you finish a route the whole thing is available to you for whenever you want to access it.