Here is the full list of all 23 My Lovely Stepsister achievements.
good ending
normal ending
bad ending
reach 20 relationship with Tracy
reach 20 relationship with Sandra
reach 15 relationship with Margot
reach 80 relationship with Tracy
reach 90 relationship with Sandra
reach 90 relationship with Margot
lose mini game
success on peeping tracy
success on peeping Sandra
success on peeping Margot
success on peeping Sandra and Margot
get wine for free
get ointment for free
click fire button
fix sink first try
finish day 5
finish day 9
finish day 12
choose Tracyβs panties
choose Margotβs panties