Before you meet Airi & Kyoko, you need to check the poster in front of the café.
As for Sakura & Reina, you need to make Reina obsessed with you, and she will show up at the café when you have a date with Sakura.
Desire will reset if you make the girls climax or have sex with them. It can only be increased through foreplay without continuing to intercourse. But don’t worry, the desire stat is not used yet.
And if there are no more quests showing in the panel, that means you’ve already cleared all the content of that update.