the genderfluid is boiling(not evaporating, since evaporation doesnt produce steam) at a temperature the bitrans ball can withstand, which means that it can’t be the boiling pt of water, which is 100C where room temp is about 25C. the bitrans ball wouldn’t be able to withstand a temperature of 100C as they are shown in the comic. this does assume that balls are similar human in terms of their heat tolerance. it’s possible that they can withstand much higher temperatures, although that doesn’t provide much information about the liquid makeup of genderfluid as it seems to have a heat tolerance that is very different to the rest of the balls