The Collaborative International Dictionary of English v.0.48:

Unromantic \Unromantic\
   See romantic.

WordNet (r) 3.0 (2006):

unromantic
    adj 1: neither expressive of nor exciting sexual love or romance

Moby Thesaurus II by Grady Ward, 1.0:

123 Moby Thesaurus words for "unromantic":
   arid, authentic, barren, bona fide, candid, card-carrying, common,
   commonplace, dinkum, down-to-earth, dry, dull, earthbound, earthy,
   flat, following the letter, genuine, good, hard, hard-boiled,
   hardheaded, honest, honest-to-God, humdrum, inartificial, infecund,
   infertile, insipid, lawful, legitimate, lifelike, literal,
   matter-of-fact, mundane, natural, naturalistic, ordinary, original,
   pedestrian, plain, poetryless, positivistic, practical,
   practical-minded, pragmatic, prosaic, prosing, prosy, pure,
   rational, real, realist, realistic, reasonable, rightful, sane,
   scientific, scientistic, secular, sensible, simon-pure, simple,
   sincere, sober, sober-minded, sound, sound-thinking, staid,
   sterling, stolid, straight-thinking, stuffy, sure-enough, tiresome,
   true to life, true to nature, true to reality, unadulterated,
   unaffected, unassumed, unassuming, uncolored, unconcocted,
   uncopied, uncounterfeited, undisguised, undisguising, undistorted,
   unembellished, unexaggerated, unfabricated, unfanciful, unfeigned,
   unfeigning, unfictitious, unflattering, unideal, unidealistic,
   unimaginative, unimagined, unimitated, unimpassioned, uninspired,
   uninvented, uninventive, unoriginal, unpoetic, unpretended,
   unpretending, unqualified, unromanticized, unsentimental,
   unsimulated, unspecious, unsynthetic, unvarnished, vapid, verbal,
   verbatim, veridical, verisimilar, word-for-word, worldly