This is a snippet of what I'm working on, you probably all saw the sketch version of the full animation already.
Now that I use a tablet, I had to relearn pretty much everything. I still don't use key frames, but I may try that in the next animation. It simplifies a few things, but my brain capacity is already at it's limit with all the things to keep track of XD
ATM, the whole layer with Richard has line art and I'm halfway done with the penis layer too. I hope to finish today all the line art and then tomorrow the colors. Adding colors is surprisingly simple, just take a color, use the fill tool, and bang. as long as the lines are closed (you can see some support lines at the bottom of Richards shirt), the parts can be colored with a click. So the biggest part that took pretty much the past days ways the line art with corrections (you can see the sketch in the background, it really needed a LOT of correction XD).
For the line art I use vectors, which is fortunately very similar to the vectors I used to draw in by mouse in the past. I can easily correct ans reshape them and they stay sharp.