Gender alterations had become so easy that some people had gone through it without notifying their significant other prior to visiting the clinic. Whether they did it due to a life long desire, simple curiosity, or they happened to walk by the clinic and decided why not, the sudden change could cause stress on a relationship.
As a counter, the clinic began offering a two for one special for couples who arrived together to receive their sex changes. The revelation that this deal existed usually made people in a relationship who hadn't already discussed it with their partner rethink if this was something that should be a surprise.
In fact, if the clerk hadn't told Vincent's girlfriend about the deal he would have been in for a terrible shock when he got home. Eliza had walked in ready to become a man when the clerk began listing their deals. That's when she realized it wasn't something she should spring on Vincent.
Afterwards, the two had a long discussion about and she eventually talked him into going through it with her. While the clinic had been around for awhile, it was still odd for Vincent to approach the front desk with his girlfriend knowing that he would be leaving as the girlfriend. All of this because...