how-do-i-love-thee
Explanation
The Joke
A woman romantically quotes the famous Elizabeth Barrett Browning poem: "How do I love thee? Let me count the ways." There is a pause, and then she asks, "Are you counting in your head?" The man sheepishly admits, "Yeah. A lot of the ways are kinda gross." She responds with a disappointed "Oooh."
The joke takes the classic romantic poem and treats it literally. Instead of the poetic metaphor of enumerating the many dimensions of deep love, the man actually starts mentally cataloging the specific ways he loves his partner -- and discovers that many of them are sexual or otherwise embarrassing when made explicit.
The Humor
The humor works by colliding high romance with awkward reality. The Browning poem is one of the most famous expressions of love in the English language, meant to evoke the boundless and transcendent nature of devotion. But when the man takes the invitation literally and actually tries to enumerate the ways he loves her, the result is not poetic at all -- it is a list that apparently includes a lot of physical and potentially embarrassing items. The comedy is in the deflation: romantic poetry assumes love is all spiritual depth, but when you honestly inventory the ways you love someone, the list gets uncomfortably corporeal.
References
"How Do I Love Thee? (Sonnet 43)" is a poem by Elizabeth Barrett Browning, published in her 1850 collection "Sonnets from the Portuguese." It is one of the most widely quoted love poems in the English language, beginning with "How do I love thee? Let me count the ways. / I love thee to the depth and breadth and height / My soul can reach..."