By Chhavi Nanda
Legend has it that the feast of Saint Valentine might be based on myth — simply a Catholic invention meant to take the place of Lupercalia, a pagan holiday celebrating fertility. Chaste saint helping Christians marry? Or half-naked forest people drinking wine and wearing goat-skins? We'll take the half-naked forest people. But since goat skins are so hard to come by these days, we've decided to honor our pagan past in a contemporary way, with an ode to lingerie, the unofficial uniform of modern heretics. The saints can keep their flannel pajamas and cotton nightgowns. We prefer the garters, thongs, bustiers, and bootie shorts in the city's best temples of temptation.
There's a good reason Dollhouse Bettie is a perennial favorite for those who love what goes under clothes: the vintage and vintage-inspired offerings are beautiful, flattering, and reasonably priced. Fans of the '50s will love the New Old Stock Exquisite Form ($89), a strapless corset with soft white cotton peaked bra cups, expanding spiral steel boning, and intricate details like lace mesh and satin ribbons. Looking for a full ensemble? Add an all-lace wrap ($127.50) with long, flowing sleeves and flowery embroidery, perfect for a dramatic unveiling or for slightly more cover during your postcoital cigarette.
1641 Haight, SF. (415) 252-7399, www.dollhousebettie.com 
If your style is a bit more black leather than white lace, you'll love Felicity's Fetiche, a delightful boutique branded as "apparel for the uninhibited" and geared toward professional dancers. This is where you'll find costumes, bright-colored fishnets, sexy tank tops, and even affordable leather items like the OverBust Busk-Front Leather Corset ($22), many of which come in plus sizes.
1214 Sutter, SF. (415) 474-7874, www.felicitysfetiche.com 
Don't be deterred by the fact that Aricie Lingerie is in a mall. This local shop's selection of European items can't be beat. One of our favorites is the Sublime Silk Chemise ($299), a sexy, sophisticated take on the little white dress by Lise Charmel, one of France's premier lingerie houses. Sure, it isn't cheap, but neither are you.
50 Post, SF. (415) 989-0261, www.ariciesf.com 
INJEANIOUS LOUNGEOf course, sexy undergarments aren't just for the ladies. You can find everything sultry and silly — from break-aways to short shorts, from comic-book undies to banana sacks — at the Castro's Injeanious Lounge. We especially like the offerings from Ginch Gonch ($20–<\d>$30), a line of "youthful underwear with an adult flare" (think hearts, trucks, or jungle themes).
432 Castro, SF. (415) 861-3963, www.injeanious.com 
Another good bet for the boys is the signature Bandito ($5) from Artificial Flavor, a comfortable, form-fitting brief that comes in rich, vibrant colors with complementary color piping. The Cole Valley shop sells clothing too, just in case you want to carry your style from the bedroom to brunch.
912 Cole #208, SF. (800) 961-6705, www.aflavor.com 
And finally, if you're hell-bent on shopping at a store that's not locally owned, we'd have to recommend U.K.-based Agent Provocateur, owned by Vivienne Westwood's son. We can't help but salivate over the Love Cream Love Garter ($50), a delicate lace piece with cream embroidery and silk ribbon detail. Or, for darker moments (in our millionaire dreams), we'll take the Telescopic Whip ($590), a retractable accessory with a snap and wrist-hold made from metal and available in either black or red. BDSM on the go? Yes, please.
54 Geary, SF. (415) 421-0229, www.agentprovocateur.com