Here is the full list of all 20 Frisky Business achievements.
Collect every piece of evidence
Complete a play through with no sexy times
Be nice to Charlie
Be nice to Charlie and Samantha
Get the true ending
Get it on with all the girls
Threesome with Balbina and Serena
Have Threesome with Jenny and Gertrude
Dated Balbina
Dated Jenny
Dated Lucy
Get it on with Tiffany
Get it on with Claire
No Wrong Answers in Trivia
Piss off Balbina
Peep through all the girls windows
Be a Jerk to Sam and Charlie
Break the 4th Wall
Get all possible endings
Get it on with Jenny X4