Writer here. The idea in Before You isn’t that Maya literally wants the ex back. What she’s doing is testing Jamie. She’s pulling up those old moments, reframing them, and giving him control over how they play out now. Constantly going between jealousy and arousal is the core of it.
Lexi’s more of a catalyst for now. She’s their close friend, someone both Maya and Jamie already trust, so her part is open and able to shift the dynamic between them. She teases, provokes, and pushes both of them to confront what they actually want, even when it feels confusing. It’s meant to blur the line between NTR, desire, and intimacy, so yeah, it’s messy on purpose, and you can expect Lexi do some crazy things.
The idea is that it gets more intense as it goes.