"Robin 101" is the third episode of the fifth season of the How I Met Your Mother TV series and 91st overall.
After Robin protests, Ted criticizes Barney for his behavior and tells him that if he does not improve, their relationship will not last.
Marshall decides to get rid of a barrel he named Mabel that he used for years as a nightstand.
He was saddened when he had to get rid of it due to Lily's "barrel resin allergy".
Ted mentions how Barney usually tries to get rid of women after one night, but was amazed to find him try hard to keep Robin around.