Like "Cuticle Tantei Inaba" before it, Strange+ is a "gag comedy" about a detective agency that, for the most part, really doesn't do much detective work.
Nothing really gets explained herein: Kou finding Takumi and what had happened before that. Miwa outside being a pair of boobs. How old Dorothy really is, and her connection to Ozu. And Rusty Nail not having her own show.
It's a gag comedy where the creator(s) behind it expect you to laugh and not much else.