This is the best promotional video I have ever seen, and all without spoiling a single second of the third season. To put it simply, it shows off why you'd want to watch the next season by adapting a chapter of the manga as it own 9 minute PV. Usually a pv is just a bunch of scenes and shots cut from the main anime to act as a teaser, this isn't. In effect this is effectively half of an episode.
It is absolutely hilarious and showcases the care and thought the studio puts into each episode in regards to the comedy part of this romcom. Genuinely, this is a PV you should put into the watch order because it's so damn good.