what's your favorite aspect of world-building and/or character design?
World Building: Lore writing. Working out the kinks in a world, getting it to match the vague storyline I often have in mind before I even get the characters! From developing more realistic settings such as my Aftermath storyline, which is just Earth but where humans have vanished and nature is reclaiming all (this is more a fun way for me to bring my university research years back into a way I find fun - looking at how climate change can impact the world as it, and how humans have impacted what currently exists), to my more unrealistic storyline of Kirat, a world of advanced feral felines located in the fictional Elysian System, which is part of the real Sunflower Galaxy. The more I can spend building a world, the more I get involved and the closer I am to not dropping the storyline.
I have a whole collection of abandoned storylines that I just couldnt get into as deeply as these two now.Character Design: I dont visually design many characters per say - I think the only one I personally visually designed is my giraffe Flam, and even then she is a normal giraffe

However, I love collecting characters that I feel fit with my world building! This is probably why I have so many characters I no longer use tbf, they are part of dropping storylines and they dont fit in my current visions... But designing on personalities, backstories, etc; I love most parts! Depending on the storyline depends on how a character gets developed;
->Flam hasnt changed in a long time in her basic traits, but her world view has changed as I have grown up. She started as very childish (cause I was a child when I first made her), but as I have aged, so as her view on the world; more mature and understanding.
->Then there are my cats of Kirat; Alix and Robin were friends, who became partners in crime, who became lovers, who become enemies in an over-exaggerated lovers quarrel that consumes a whole city. Its a twisted storyline, but I loved it.