People love to collect in The Elder Scrolls V: Skyrim. They collect loot, they collect books, horses and armour. They even collect butterflies in jars. But this guy (I'm assuming he's a him because most serial killers are) likes to collect the bodies of decapitated female companion characters and undress and pose them.
It's just a video from a video game. But the music combined with the fact that this walk-through of a house decorated with the posed, headless bodies of women, is called "Skyrim sex life". makes it feel like something a bit darker.
[Thanks Adrian and Paperghost!]