The VIP system is an optional, premium account setting that costs requires spending real money to use. Some of the features are quite nice, but none are considered “must haves”. If you don't have money to spend, don't feel pressured to use the system. If you do have money to spend, they are a nice little perk on top of whatever it is you're actually buying.
VIP points are earned by making in-game purchases. Each VIP Level requires a certain number of points to reach, and each level unlocks additional benefits and may improve existing benefits.
Some VIP benefits are only available when your VIP status is “Active”. Your VIP time is how much time you have left until your VIP status is inactive. Once inactive, you do not lose VIP levels or points, you simply stop benefitting from some of the perks. You can buy extra time directly, but this is not recommended unless you have a lot of disposable income. You can also get VIP time with some, but not all purchases.
These benefits are always available, even when your VIP status is Inactive. The Flirt Energy boost is quite handy.
These benefits are only available when your VIP status is Active. Most are nice, but minor benefits. Some of the most beneficial are the Additional Builders, the Roulette Rewards Multiplier, and the Daily Nanites.
There are four H-scenes unlocked by VIP levels. Once unlocked they are permanent. These scenes are the only content that is paywalled in the game.