@
althworld
I added this to my FAQ which is attached. I PMed you a copy. Be aware that there are many spoilers! I hope this helps.
9) How do I buy things in the game?
The economy is based on Holiday Island favor points or just HI points. You gain these points by collecting sperm samples and turning them in to the doctor. The doctor will gain favor: one point per sample. You will be awarded HI points. There are three kinds of sperm samples: high, where your lust was high when it was collected, listed in your inventory as sperm (h) vial; low, where your lust was low when collected, sperm (l) vial, and enhanced high, where your lust was high and you were under the effects of the blue pill when collected, sperm (eh) vial. When you turn the samples in, you will get half as much for low than for high. You can receive a blue pill with enough high samples and a green pill for enough low samples. Eh samples are used to complete quests to gain access to girl's information from their implants. Eventually, 100 HI points can be obtained each time you beat Joy at poker.
Once you gain HI points, you can quickly spend 50 points to buy a watch from the doctor which will monitor your vitals and can later be used to track the girl's stats. Sometime later, Joy will send you a letter about a shopping app which will be added to your phone which you can use to buy pills, gifts, binoculars, a new phone, a battery charger, beauty products, and clothing. Knowledge of a girl's measurements will be necessary in order to buy clothing. Sometimes you will need to have the receptionist unlock access to certain items.
I hope this helps.