Yes, "Drinking Buddies" was primarily improvised. Directed by Joe Swanberg, the film features a cast that includes Olivia Wilde, Jake Johnson, Anna Kendrick, and Ron Livingston. The script was loosely structured, allowing actors to improvise their dialogue and interactions, which contributed to the film's natural and authentic feel. This approach is characteristic of Swanberg's filmmaking style, focusing on character-driven narratives and real-life dynamics. The improvisation helped to create a more genuine portrayal of relationships and social interactions.

At the end of "Drinking Buddies," the dynamics between the characters reach a turning point. After a weekend trip where feelings intensify, Luke (Jake Johnson) and Kate (Olivia Wilde) share a moment that suggests a deeper connection. However, they ultimately decide not to pursue a romantic relationship, acknowledging their current situations with their respective partners. The film concludes with both characters returning to their lives, hinting at the complexities of relationships and the importance of friendship.

"Drinking Buddies" is rated R primarily for its strong language and sexual content. The film features frequent use of profanity, including explicit language that may not be suitable for younger audiences. Additionally, it depicts adult themes related to relationships, infidelity, and alcohol consumption, which contribute to its mature rating. The film's realistic portrayal of adult interactions and situations further reinforces the R classification.

In "Drinking Buddies," Kate and Luke do not explicitly sleep together, but there is a strong romantic tension between them throughout the film. They share intimate moments, and their chemistry is evident, especially during a weekend trip. However, the film ultimately leaves their relationship ambiguous. Kate is in a relationship with another character, Chris, which complicates her feelings for Luke. The film focuses on the complexities of friendships and romantic relationships rather than providing a clear resolution to their potential romance.