Walkthrough:
- Finish Karen beach events.
- Wait till night, go to Karen room.
- Next morning go at 2 floor.
- Wait till night.
- Go to Karen room.
- Next morning go at 2 floor.
Now you have more options with her in some events! 
(Morning kitchen, in her room at afternoon, at the beach, and when you enter bathroom at afternoon! 
Also, there is a repeatable event in her room at night!)