If you a single chick and on valentines day, 14th February, you are at home alone, sitting and fingering herself while crying, the chick is having a vagintines day with herself.
This is the name given to a person who takes the viginity of someone else. They themselves may also be a virgin, in that case both of the partners who partake in a bit of hanky panky are themselves virginsteins for taking their partner's virginity away from them.
A woman made love to a man who was still a virgin then later she said afterwards 'I'm now your virginstein!'