Official accounts of 毎日ヒトコト英会話 (Everyday's "One Sentence English"), a joke English learning website. According to the site's information, it has two main illustrators.
Site name: 毎日ヒトコト英会話 (Mainichi Hitokoto Eikaiwa)
Artists: ゆっきー (Yukkii) and こーちゃん (Koochan)
https://www.pixiv.net/users/13666882
https://www.pixiv.net/stacc/hitocoto_e
https://twitter.com/hitocoto_e
https://twitter.com/intent/user?user_id=3023400499
https://seiga.nicovideo.jp/user/illust/46500808
https://www.nicovideo.jp/user/46500808
https://sketch.pixiv.net/@hitocoto_e
https://www.facebook.com/hitokoto.eikaiwa