As mentioned by LaPlace, Rahel doesn't have a romancing event yet, however you should encounter Lanch's first event at 500 points and his second at 800!
I believe Tarius has only one milestone so far? Again im sorry if i'm mistaken haha, if it helps though, in the cheat menu there is a cheat in easy mode to boost the relationship, so you can add 500 or 1000 to your relationship with any desire! To get the cheat menu press Q in game to open the menu, (the porting is to teleport anywhere on the map), hit cheats and you can find the relationship cheat at the bottom XD