surreptitiously, insidiously, sneakily, furtively, discreetly, cunningly, covertly, quietly, noiselessly, clandestinely, silently, slowly, brazenly, purposefully, cleverly, craftily, subtly, shrewdly, secretly, remorselessly, unobtrusively, adroitly, effortlessly, methodically, inexorably, skillfully, discretely, skilfully, unnoticeably, unsuspectingly, invisibly, agilely, malevolently, inconspicuously, nimbly, clumsily, deftly, menacingly, unhurriedly, smartly, laboriously, systematically, merrily, industriously, imperceptibly, creakily, shamefacedly, deviously, swiftly, unwittingly, covetously, nefariously, soundlessly, gradually, slickly, dutifully, submissively, assiduously, hurriedly, casually, shamelessly, briskly, unconsciously, inexpertly, deceitfully, greedily, unwillingly, ineptly, unbeknown, nonchalantly, secretively, incrementally, fastidiously, mendaciously, ruthlessly, unknowingly, intrusively, ingeniously, dexterously, frenetically, unscrupulously, slyly, languidly, absentmindedly, ostentatiously, determinedly, sophisticatedly, purposelessly, cumbersomely, fluidly, masterfully, obediently, suavely, rampantly, furiously, mysteriously, mischievously, glacially, expertly, expensively, malignantly, jerkily

., creep, creep up, haunt, hugger mugger, mouse, pussyfoot, skulk, slink, slip, slip away, sneak, sneak away, sneak off, sneak out, sneak up, stalk, stalking, steal, steal away