Take this from danbooru, so credits to whoever put this information.
-An employee of Nitroplus. He has two different nicknames to separate commercial work from doujinshi. Circle: パンダニク (Panda-Niku). The other main circle member is やきにくATK (Yakiniku ATK). Often confused with said circle member, なまにくATK (Namaniku ATK), in commercial work crediting.
Name used for commercial artwork (Nitroplus): 大熊猫介 (Ookuma Nekosuke) Name used for fan artwork / doujinshi (Panda-Niku): JCパンダム (J.C. Pandam)