Working will earn Stars and Player EXP.
Hourglasses can be used to reduce the amount of time spent working.
Help Out Edit
If your boyfriend is Helped Out by someone while he Works, you will earn extra Stars when the Work Ends.
Also, if you Help Out other player's Boyfriends while they Work, you will earn Stars and EXP too. Helping Out a Friend will earn you more stars and EXP than usual.
Help Out can only be used once per Work. If the other player's Boyfriend completes their Work and starts another, you will be able to Help Out again.