Arawi Keiichi's brain moves too fast for normal TV, so this ONA is just him unleashing pure comedy momentum for seven minutes straight. The Nichijou cast becomes an excuse to riff, not a story to follow, absurdist escalations that don't care about landing jokes so much as the energy of throwing them. You watch because the creator's joy at drawing ridiculous things is contagious, and because sometimes anime is just someone saying "here, have something weird and harmless."
Arawi Keiichi Tanpen is a one-episode comedy short released online, created by Arawi Keiichi. The short brings back characters from Nichijou for a brief comic outing, so fans of that work will recognize the faces here. At a single episode, it makes for a quick, light watch for anyone curious to see those characters again in a small comedic piece.