Aliasia answered Cadis by trying to caress him, before remembering there was nothing, identifyable, to caress.  She answered with tears when his storm of sex hurt her.  If Cadis has a way to sense fear, by taste or otherwise, then she answers with fear when he threatens to wait out the spell.  She answers by not trying to escape.  By embracing it, cumming hardest when her breasts and clit are being twisted, when the walls of her sex and bowels feel like they're about to burst, when the stinging chemicals make her fear dissolution most.<br/><br/>Then Cadis realizes a limit of the spell. Respiration is limited, designed around "cum, then afterglow" instead of "running a constant sex marathon".  By keeping her cumming he'll soon induce fainting.  In fact, he notices that she's already reacting like an autoerotic asphyxiant, cumming harder and getting more turned on as she runs short on air.  If he keeps pounding away, keeping her in constant orgasm, she'll faint very soon.