Minato Aqua debuted as a second generation Hololive VTuber in 2018 and built a following around maid themed streams, gaming and singing. Her phrase mou neru translates roughly to already going to sleep, and this recording spread through clips and soundboards as a reusable goodnight reaction. Fans pair it with other cute anime voice lines like Tuturu when building reaction folders for chats and edits. Its lasting appeal comes from Aqua's instantly recognizable voice and the universal, low effort humor of dramatically logging off for bed.