These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Les Yay: Occurs in the songs where there are twoRins. In South North Story Rin and Riliane get very intimate with each other and in Screws, Gears and Pride the two Rins pretty much give each other the "it's not you, it's me" speech when they part ways.
Magnum Opus: Story of Evil. Servant of Evil in particular, from the Evillious Chronicles. It's the song that gained mothy his producer name in the Vocaloid fanbase, after all.