Note: "Stubborn people hoard many goods and evils"; "Stubborn people" is using a word that specifically refers to people who insist that you have to fulfill any obligations one has or uphold ideals, no matter what.
"Dr. Duran Duran" is a reference to the 1968 film Barbarella, which follows a space adventurer who is sent to another solar system to find Dr. Durand Durand, who has invented a laser that Earth's leaders believe could destroy all of humanity. Durand is one of the villains, but it also has another in a tyrant queen that he works under, who is a lesbian. It recieved some critiscism for being overly explicit. And yes, this is the same movie that the english band Duran Duran got their name from.
"Hey, you know a writer named Ranpo?" refers to the japanese writer Edogawa Ranpo, who is most known for popularizing the mystery genre in Japan. One of his novels, KotÅ no Oni, actually has a gay man as one of the main characters, and he also wrote several essays on the topic of gay romance. Side note, Teniwoha's Twitter username also references Ranpo (@edogawa_sampo).
A "1LDK apartment" just refers to a one bedroom apartment. It probably took me way too long to figure that out.
Fun fact: Kohane's voice actress, Akina, and An's voice actress, Sumi Tomomi Jiena, have done covers of this song. Also, funnily enough, Mizuki's voice actress, Satou Hinata, also did a cover of this prior to it being added to PJSK.