Subtext rhymes with:
datext, hypertext, pretext, videotext, datext, hypertext, pretext, videotext, affixed, akst, angst, anikst, annexed, axed, axt, bakst, baxt, betwixt, blixt, boxed, climaxed, coaxed, context, datext, faxed, fixed, flexed, flummoxed, hext, hoechst, hypertext, indexed, intermixed, kekst, maxed, mixed, mixte, next, nixed, outfoxed, overtaxed, perplexed, pretext, relaxed, sexed, sixed, taxed, teletext, text, transfixed, unmixed, untaxed, vexed, videotext, waxed, xeroxed
Subtext sounds like:
sabatista, sabotaged, softest, speedskate, swiftest