Before Sunrise
"What about a rational adult decision ?"
ABSOLUTE BANGER.
This movie portrays so accurately love between naive young people exploring their thoughts about life's meaning, dealing with time, wanting to put the world to rights etc.
Celine and Jesse might be different, yet they reunite in a brief but intense journey in which they exchange both simple and deep interactions knowing they'll utltimately have to part.
Despite the few teasing comments (used as a serious way to communicate) they made about behaving like adults, they end up leaving each other on a childlike promise.