For Maso grind, a good method is engage in Gangbang or Three-somes,my preferred method:
Go to school and enter you gender opposite washroom-with decent enough
Promiscuity(lvl2) you should get an option to Seduce them(leading to a consensual encounter)-Choose bratty or defiant option to anger them-Rinse and repeat-you can do it multiple time while also taking brakes-At the start of school before Science class/During Recess/By skipping Pool classes/After finishing Pool classes....etc.
Wear skullduggery mask if you want to avoid gaining fame in Negative stats like
Sex FAME etc or if you want to rob them during encounter to lvl up skullduggery , To prevent them from removing your skullduggery mask during encounter use the
ASK function and select "to leave your mask on"(they can still try even after saying this so make saves in middle).Their is a high possibility that they will try to choke you which also helps in getting the
Asphyxiophilia trait(oragsm 35 times while being choked).
You can also try entering the opposite gender changing room naked just before Pool classes which will start a consensual Gangbang but it is much harder to control them(like most likely they will take off you skullduggery mask before you can even ask them to not to) Also it requires a high lvl in both
Exhibition and Promiscuity to start the gang bang and it will also net you
Delinquency.. So in my opinion Washroom method is much more stable and manageable while also less demanding in stats.