So, after a lot of debating (sorry for the late start-- I was participating in GB Jam 5 until the 10th and then spent a week polishing my entry over there), I actually am trying out GameMaker Studio as a possible engine for this.
Here's the general plan:
You, the PC, are a member of a local Adventuring Guild in the town of Westfen*. About ten years ago a nearby fortress, Castle Linmeadow, was sacked by orcs**, and it's believed that some powerful artifacts remain inside the castle, abandoned by the people who managed to flee before they were killed.
The Adventurer's Guild has been chartered by the town's mayor to go try to retrieve those artifacts. As the PC, you and your NPC party go on a short trip to try to retrieve those artifacts. Gameplay will mostly involve talking and traveling to and from the castle, exploring it-- trying to re-create something similar to the D&D style experience of a group of adventurers traveling the land and presumably trying to do good as they go.
* - Names subject to change, especially this one.
** - orcs are 100% a placeholder unless or until I can think of a less-generic Threat that might've been responsible for the sacking of the castle.
In the long rung I'd like to make it possible to romance all of the characters, but for Yuri Jam limits I'm aiming for just one viable option by the deadline so I don't accidentally bite off more than I can chew!
So far I've grabbed a movement code engine from HeartBeast (since YGJ's main rule is just to have a story about queer ladies and their relationships, I'm trying to focus on making the writing as high quality as possible), and programmed in a cursor-selecting menu for branching choices between gameplay and dialogue moments. I feel a little like I might be re-inventing the wheel on the latter part, since Ren.py handles it so much more smoothly and intuitively, but I wanted to give it maybe a couple of days of research on the Game Maker front, since a previous tool did not pan out for the length of this project.
I feel like I'm joining a race in the third lap, but here are some of the character sketches I did in earlier design, while still trying to determine the NPC party's personalities / skills / hobbies:
Goals for tomorrow:
-Get the menu interface for choice-making fully functional
-Implement the barebones skeleton of the choices that occur over the course of the plot & test it out