I am not sure if this is a accurate solution but i am going to share what worked for me.
1. press cn_Y anytime while playing
2. select the third option 'calendar'
3. choose any day (Current day also works)
4. press cn_A to open sub menu
4. Choose 1st option out of the 6 options
5. repeat the process until you choose all the options at least once (Choose any costume when asked on selecting last option)
Note: My 5th option was not highlighted (Maid achievement). It got highlighted after celebrating 2nd anniversary (i chose the very first girl) on 30th Nov. I don't know what triggered it either the completion of 2 years or it is only selectable in later months of the year.
This will unlock several other achievements as well.
Hope this helps.