Here's what rhymes with pessimo.
no know mo mow noe so go though low show co snow row tho fo foe ho lo bo doe dough po ro toe wo woe tow yo beau ceux faut goe hoe jo ko sew soe uno vo beaux cho dau roe sho yeux zo rho whoa doh schmo schmoe below ago flow blow grow slow throw pro glow quo fro chateau crow hello thro bio nouveau escrow floe tuo bro chateaux dunno stow throe trow chapeau sloe deathblow foreknow kayo chapeaux although audio bestow buffalo folio indigo dynamo forego forgo vertigo aglow cameo dicho domino medico siglo topos kapok oleo piccolo tarot turbot bandeau gateau matzoh fatso gateaux pekoe borzoi romeo resew ratio radio embryo overthrow plateau studio undergo overflow patio stereo polio politico propos tableau aliquot mistletoe outgrow presidio rodeo spatio tableaux oregano plateaux trousseau adagio pianissimo undertow overgrow regrow pompano trousseaux tallyho portico bungalow calico apropos afterglow pistachio microdot portfolio generalissimo mustachio moustachio archipelago impresario braggadocio