So yeah, I actually managed to get this out fairly quickly, for me at least. Been experimenting with stuff to get faster, lineart especially, and I like how it came out. Would've had it out sooner if I didn't have (and still have) a fever while making this, and there's already plenty of pics like mine to beat me out. Ah well. ¯\_(ツ)_/¯
And for anyone wondering, I only slightly used a vector for the logo on the shirts. The owl's from the vector, but the letters were hand drawn, since they still look sloppy and all. SAI doesn't have a function yet where you can bloat out images like Photoshop, so hope SAI 2 fixes includes that.