There is no widely documented film, show or viral video behind this particular clip, so it is best understood as a soundboard reaction rather than a quote from a known character. Affreuse is the feminine form of the French adjective for dreadful, horrible or awful, and that blunt meaning gives the clip its comic force even for listeners who do not speak French. Short, single-word reactions travel well online because they need no translation or context, and this one survives as a quick, reusable judgement for anything from a fashion fail to a prank gone wrong.