I only know a few of them, so I'll answer the ones I know

1. Who is Hacken Lee's and Jessica Hsuan's best friend in the first chapter?
Emme Wong

3. Who else likes Chris Wong besides Jade Kwan in the third chapter?
Annie Man

4. What does Kelly Chen do in the fourth chapter?
Author

5. What is Mandy Cho's and Aaron Kwok's occupation in the fifth and sixth chapter?
Mandy is a model and Aaron is a fashion desginer.

6. Who is Kelly Chen's friend in the seventh chapter?
Fiona Yeun

7. Who are the three guest stars in the eighth chapter?
Edmond Leung