stumbled over this by chance - and I am impressed, well-written, different chars, a plot I want to follow and good visuals (only the animations loops could be slightly longer and smoother).
the gui and UX is generally nice, with one exception: too many chars to follow, and I *always* forget whose story line I already finished :)
as introducing a new variable is probably overkill I abused your hint system: if "<char>hint1" starts with "You have seen all" I added an overlay to the character card overview. Visually not the best approach (better is maybe something like a green check mark), but you'll get the idea.
the blue ones are my addition, triggered with (more or less the same idea as the yellow borders you already use)
if gertrudehint1.startswith('You have seen all '):
add "affectionmenudone.webp" xalign 0.03 + (platexspacing*2) yalign 0.1
