Mmm, well you could make an onKill script, and set an addEvent to remove the blood stain after a few milliseconds.
You use an addEvent, so that it happens after the creature has fully died.
Lua:
local function removeBlood(pos)
if getTileItemById(pos, itemId).uid > 1 then
doRemoveItem(getTileItemById(pos, itemId).uid)
end
end
Lua:
addEvent(removeBlood, 1, pos)