If you’re tired of going to bed with flabby, self-important books that push you into long-term commitments and rarely deliver on their promises, treat yourself this Valentine’s Day to a box of Godiva chocolates and Simon Rich’s hysterical new story collection, “The Last Girlfriend on Earth.”

It just might be the best one-night stand you’ll ever have.

Divided into three sections – “Boy Meets Girl,” “Boy Gets Girl,” “Boy Loses Girl” – the book’s lean sketches range from the bizarre (a magical, natty goat falls hard for a little English girl) to the deliciously profane (a priest unleashes his inner “bro” to exorcise the ghost of an ex-girlfriend).

Some of these tales have appeared in The New Yorker. All of them will remind you that, when it comes to a good story, size doesn’t matter.

In fact, the book’s best pieces are no longer than a few pages.

“Dog Missed Connections,” Rich’s hilarious canine variation on the wistful, occasionally creepy Craigs- list category, might deliver more laughs per word than anything you’ll read this year: “Saw you by the Dumpster, eating a pile of what appeared to be human vomit,” posts w4m; “Astoria, alley behind Taco Bell. You seemed like someone who doesn’t take himself too seriously.”

The book’s first story, “Protected,” is an oddly warm tale about a sentimental young man negotiating love’s battlefield.

It’s told through the eyes of a prophylactic living in his wallet.

“When I wake up next day, Jordan is dangling me over trash can,” the condom says one morning, still in its wrapper. “Suddenly, though, Jordan carries me away – to other side of room. I am placed inside shoe box under his bed.”

The son of former New York Times columnist Frank Rich, the author was the second-youngest writer ever hired by “Saturday Night Live,” and his parodies are top-notch.

“The Adventure of the Spotted Tie,” for example, gives us a Sherlock Holmes who can detect anything but his wife’s infidelity.

In “Occupy Jen’s Street,” a movement rises up against the “entire romantic system”: “Ninety-nine percent of men are in love with the top one percent of women,” says the ringleader. “And yet they often refuse to date us. It’s a complete injustice.”

Let’s give the last word here to Xander, a scientist in Rich’s zany, touching story “The Present,” who’s gotten one too many impersonal birthday gifts for his girlfriend.

He establishes himself as perhaps the book’s most sympathetic character when he makes this realization: “Quantum physics and nuclear hydraulics were trivial compared to the rigors of gift shopping.”