It starts with Cindy putting a photo of Gladio in her shop, hoping that it might act as a leering creep deterrent, and escalates to stealth fake dating until one she greets him by latching onto him and calling him pet names to keep up the ruse and Gladio's like "When the fuck did this happen?"

It can be endgame Cindy/Gladio, or Gladio could already be in a relationship with one (or two or three) of his bros, and this situation is just super awkward. I'm good with either.