"The plot prioritizes and the psychological 'push-and-pull' between the lead characters." Fun "Trope" Style Labels "Fluent in sarcasm and soulmate-coded stares." "The 'Stop Looking At Me Like That' starter pack."
Depending on whether you are writing a story, a social media caption, or just describing a specific vibe, here are a few ways to phrase the idea of "teasing relationships and romantic storylines": For a Story Summary or Blurb teasing teensex
"Plot twist: The teasing was actually the foreword to a love story." Descriptive Academic/Critical Phrasing a social media caption