To slay through the day is to perform exceptionally. For Gen-Z, slay could be anything, from a greeting, compliment or a replacement for regards at the end of emails.
BT is the short form for Bad Trip. That is, a bad memory from the past which is revived due to an event in the present day.
Adrian Mutu (Romania)
If you heard 'stop being a simp' from some Gen-Z person, it simply means they perceive you to be doing too much to woo a person you like in a one-sided desperate fashion.
Dank means high quality. It is mostly an internet slang term that is also used to convey the quality of edgy memes.
Normie refers to a person who gravitates to social standards and accepted practices without broader cultural perspectives.
A situationship is like a relationship, but more of a situation. Friends with benefits are in a situationship. People who are a 'thing' are also regarded as being in a situationship.
Lit is a term used to describe something that is cool and exciting, or just generally something you would want to experience.
Boujee is slang for something "luxurious in lifestyle yet humble in character", influenced by and often interchangeable with the slang bougie.
Rizz refers to the perceived skill in charming or seducing a potential romantic partner, especially through verbal communication.