Stray Kids - Up All Night
스트레이 키즈 - 오늘 밤 나는 불을 켜

Four lovely creatures of the night sneak into an elderly couple's home. They sing, dance, hang out in the bedroom and make a gruesome cake. At the end of the night, only the grandmother remains...

So, assuming that the vampires killed the grandfather, those were his body parts they were baking into their "masterpiece" cake (hand in the blender, fingers on the cake, eyeballs on the side). Eeeeewww!
Since Bang Chan entered first and since vampires need to be invited in the house, perhaps it was his grandparents' home?
Love that Felix did BamBam's signature skrrrt-skrrt. JYP idols, past and present, represent!
Funniest line: "Perhaps it’s because the caffeine is still in my body"
An ode to insomnia...
MVP: Seungmin, for being a sweetie and thinking it might just be the caffeine keeping him up. Hat tip to Changbin for being a much-needed creepy influence in the video. I'm pretty sure Changbin is the one who actually killed the grandfather.