Lesbian kiss episode
| Lily Aldrin (Alyson Hannigan) and Robin Scherbatsky (Cobie Smulders). Robin kisses Lily to give Lily the "lesbian experience" she never had. Both are series regulars.  Robin Scherbatsky and Lily Aldrin kiss to seal an oath promising not to interfere with Barney's life. Barney and his girlfriend, Quinn, reveal moments later that the lesbian kiss was intended to humiliate the pair and teach a lesson about judgment.