That first image is an edit of HUGZzz by Irene Strychalski. She’s improved tremendously in the past nine years, and you can see her current work on her tumblr, reniedraws! She has done backgrounds for Archer and Unsupervised, backgrounds and character designs for Chozen, and pencils and inks for issue #1 of Deadpool Family. She’s currently making a webcomic called Shaman Child. Here’s some of her current art:
As for the anime girl in the plaid skirt, I braved the hellscape that is early ‘00s anime websites, exploring endless gif-covered Gaia pages and vampire-filled roleplay forums, traveling across seas of unsourced DeviantArt edits and low-res hentai, to discover that she is an original character by Hiro Suzuhira. She has done work for Shuffle!, Ef: A Tale of Melodies, Akikan!, Phantom Breaker, and We Without Wings, among many others, and she is also a prolific freelance illustrator. Here are some examples of her art:
