: This part usually represents the group or entity that encoded and released the video. In this case, "VALiS" and "EtHD" likely refer to the groups involved in making the video available in this format. Groups like these often specialize in encoding movies and TV shows for distribution over the internet.
While not always mentioned in the filename, good releases include the lossless Japanese DTS-HD Master Audio 5.1 (or 7.1) track. RADWIMPS’ soundtrack — “Zenzenzense,” “Sparkle,” “Dream Lantern” — has dynamic range that lossy codecs flatten. The bass drop during the katawaredoki twilight scene demands a subwoofer; the surround channels carry the whisper of wind through the mountain shrine. This VALiS-EtHD release typically syncs the lossless audio to the 4K video, a huge upgrade over streaming. Your.Name.2016.2160p.UHD.BluRay.x265-VALiS-EtHD-