Just Realised there are no Valentine's day events
I was thinking on this while I was trying to sleep. Of course, there would be scenes or encounters that pop up wandering around an NPCs location, like say Etheryn or Clementine stopping you in the Winter City or Hawkethorne. I was also thinking that Farrah, the blue demon cat in Wayfort (assuming you have her), approaches and tells you her latest scheme to make money, giving you a token (like a Valentine's card, but just like a velvet heart) and saying that she wants to try and create a new tradition of passing out such things (to make money and to commercialize it). She wants to leave a sort of, hallmark on the Spring holiday season. She says the Marcher Baron is the right tool for the job, so she gives them one, and I (or more people), write a valentine's card scene that appears at an NPCs dialogue menu in their normal location. (only during the event time, say February 1st to the 20th or the 28th (no plans for Leap Year).
So if you walk into Clementine's house during that time and have one of Farrah's hallmarks, there will be a 'Give Hallmark' option and maybe even a Chaste/Friendship option or a Lover option and do scenes. The Chaste one might just be a scene of spending the day together. The other one probably leads to romance (possibly one already existing sex option to save writing for some). Some people, like Kas will only lead to sex. It would require making scenes for lots of different characters (or a massive collab) to make Farrah's method an option (and the NPCs could still have their own where they approach the Champ).
You can only do one Hallmark scene with a particular NPC per event period (like Halloween or Festivus). You can only have one Hallmark key item at a time, but can go back to Farrah for more, maybe the first is 1 EP or 10 EP, then she raises it to 100 EP, then 1,000 (she's got to make money, and that's what gets her own juices flowing). If you manage to pass out 4 or more Hallmarks, after the event, maybe she sends a messenger to find you about a special, limited-time offer and making all that money, all your work, and all the attention you gained her little token idea worked and she gives you her own little special reward (will cause Corruption), or you can pass on it and maybe she gives you a free Hallmark (which can't be used until next year) but it will be one you won't have to pay for when the next event starts.
Just musings.