You should be able to finish the quest line when winning or losing against Yanki in his Assignment Quest. The game asks you if you would like to end the quest line
Viewing post in Out of Puberty: ReImagined comments
I already came across that a long time ago before I downloaded this version. If I keep choosing play game and choose either to take it easy or take serious it just gives me all the sex choices I already went through I don't know how many times. when I went to choose finish, it was during the CG where he and Pearl are sitting at the laptop.