How about a JOI-System to create a different experience every time you play it. I don’t know if this is even possible or desired to bring this in the game, but I think of something like this:

Preparation:
Randomly set the rules for this session:
- normal jerk off and cum or
- jerk off and don’t cum/blue balls or
- jerk off and ruined cum or
- jerk off and delayed cum or
- jerk off and cum eating or
- jerk off and edging or
- stop and go jerk off

Randomly set special rules for this session:
- none/no special or
- light ass play or
- heavy ass play (insert finger or jerk with plug inside) – make this optional, if sub doesn’t want that, stop the session and give him a blue crystal for punishment or
- play time (let sub interact with mistress between jerksessions)

Randomly set the length of the jerk session:
one session could be a part of 5 minutes times a random number from 2-10, to create a 10-50 minutes jerk session

Randomly set the help for this session:
- none, must jerk to fully clothed mistress in her environment
- mistress shows parts of her body (breats, ass, pussy), sub always has to worship
- mistress brings in another naked slave from other sex as sub, let slave go to different poses to help sub jerk off
- mistress brings in another naked slave from same sex as sub, let slave go to different poses to help (or make it harder)

Randomly set mistress character (changing some of her lines in the jerk-parts) and maybe give a bonus on this roll to neutral or encouraging, if the mistress is happy with the sub):
- neutral/normal
- encouraging
- humiliating

Start Session with INTRO:
(2-3 minutes), let sub jerk to make his dick hard, explain the rules (always jerk as hard and fast as told, don’t cum without permission, shake head no if sub is about to cum (to give him/her a 10-20 second break (and maybe punish him, depending of mistress character and how often it has already happened in this session)), ect.). If ass play instruct to put plug in or if light ass play instruct to caress the asshole

JERK SESSION:
(5 minutes), in these sessions, sub has to follow orders like faster, slow down, harder, lighter strokes and maybe gets encouraged or humiliated, and gets the help from mistress or the other slave.

AFTER JERK SESSION:
- if rule is edging, let sub edge 2-3mins without cuming
- if rule is stop and go, sub has to stop for 30s to 2 minutes, and put his/her hands away
- if special rule is light ass play, let sub jerk and remind sub to play with ass
- if special rule is heavy ass play, let sub jerk and play with his/her ass (insert finger or put plug out and in again)
- if special rule is play time, the sub has to play a game against mistress, e.g. rock paper scissors or so. Sub wins and gets a 2-3min edge, sub loses and has to stop jerking or even gets punished, if mistress character is humiliating

Goto JERK SESSION again until random repeat number is reached. If last JERK SESSION is complete, skip AFTER JERK SESSION and go to ENDING.

ENDING:
Let sub edge for 2-3min and explain the rules for cuming. Give a Countdown and instruct sub to go “over the edge” at 2 but don’t cum until 0.
- if rule is normal jerk and cum, or edging, or stop and go, let sub go over the edge at 2 and let him cum at 0
- if rule is blue balls, stop countdown at 5 and stop session without AFTER CARE
- if rule is ruined cum, let sub go over the edge at 2 and instruct sub to cum at 0 without hands
- if rule is delayed cum, let sub go over the edge at 2 and delay the 0, maybe 2-5 seconds, sub has to jerk but have to hold it until 0 is called by mistress
- if rule is cum eating, let sub go over the edge at 2 and instruct him to cum in/on hand, let sub eat it
- if special rule is play time, let sub play against mistress, if sub wins, he gets his release, if not, stop session without AFTER CARE

 AFTER CARE:
- if special rule was heavy ass play, instruct to take out plug
- if mistress character is “normal”, instruct to clean the mess, present to mistress and get out
- if mistress is encouraging, let sub caress his genitals a bit to get down, encouraging words, instruct to clean the mess, present to mistress and get out
- if mistress is humiliating, randomly set after care to:
o humiliating words, instruct to clean the mess, and get the f. out or
o punish sub (e.g. let sub slap the now sensitive genitals), instruct to clean the mess, and get the f. out or
o let sub jerk again (post orgasm torture) hard and fast for 2-3 minutes, instruct to clean the mess and get the f. out

this could be the standard reward scene for every mistress except for Yuki Onna and Nega Yuki, as they already have their own rewards