i tried it out a few weeks ago and even got lucky with a rainbow girl (0.5% droprate)

It plays like an rpg similar to the play style of KG/OI. You run across the map in a snake and ladder style drawing with up to 4 teams of girls, killing mobs, collecting treasures to reach the end of the map. Pretty fast run per map, about 3-5 mins.

The unique points imo, is that there is an equipment system (dumbed down version of KG's), affection system (similar to aigis) and class evolution. Pretty fun at first, but turned grindy like KG/OI for me.
The stamina regen is pretty close to aigis. So there is a longer waiting period compared to KG/OI.

If you like KG/OI, you might like FKG.