Here is the full list of all 31 Dream Date achievements.
Outdoor hot spring with mixed bath
Sensitive idol
Unlocked Yurui's CG
Have all of Yurui
The idol of hard work
Be strongly kissing
The idol is sick
This soda is all over the place!
dol is the king of the stomach!
Have all of Kashima
First touch
Find the kitten
Welcom to Dream World
Find the kitten again
Win the favor of Kashima
What kind of uniform？
Feeding of Rina
Is Rina on purpose？
Rina is jealous
Super size idol
It's a real kiss
Dispel the uneasiness of Kashima
Reward after cleaning?
Active Rina
Skilled Rina
Have all of Rina
Unlocked Kashima's CG
Unlocked Rina's CG