And that's how Cassie managed to get in without her or anyone else's future self stopping her.
TRANSCRIPTION COURTESY OF JOSEPH HOUK - (CW, seated on the bed) "So..." (BG, adjusting her top) "um..." (MG, looking over at CW) "Yyyeah." (CW) "I... just wanna know when this started." (BG) "Well, before I answer that... Are you okay with us, being in a relationship like this? I just want you to promise me you won't go back and, like, sabotage our first tryst or something like that." (CW) "Beth, you're my best friend. You're a good friend too, Matt. I would never do that to either of you." (MG, looking up) "Well, I think it was while you and Allen were in Paratopia." (BG) "We were arguing over something dumb, and... all of a sudden we were kissing and making out." (MG) "I guess we were just the classic example of sexual tension building up between two people who never expected to be attracted to each other." (BG) "Or just too busy beating up on each other to notice. And we... honestly didn't know how to break the news to you." (CW) "So. Should I just go back and stop myself from barging in?" (BG) "Naah. It's really best you found out this way."