[NSFW] Have you been involved in a hookup that turned into a relationship?

If so, how many hookups did you have before you decided it was a relationship? Was there a progression of sexual intimacy during the course of the relationship?

Let’s say you there are four general categories of sexual activity: kissing and non-intimate touching; hand to genital contact; mouth to genital contact; and sexual intercourse… on which hookup did you get to which form(s) of sexual activity?

When it turned into a relationship, how did you know/decide it was a relationship?