It’s not anywhere near as lopsided as it might seem. Perhaps if you reread earlier events, you’ll remember a number of details regarding the power balance.
For starters, this is an extremely unusual situation, they’re being taken completely by surprise deep into their lands, when normally it’s the opposite, they rely on demons being full of themselves to take the advantage. In addition, the strongest exceptional demons are normally taken care of by a wielder of an holy sword (The hero title isn’t the result of an accomplishment here). All three characters presented here are all candidates for that, but right now, they got attacked before anyone got chosen. Their joker is missing right now. To make things worse, Sharmeela & Adler were on their break so they didn’t even come with their own weapons that can withstand their stronger techniques, they might as well be bucked naked and can only take some cheap weapons from killed fodder.
Usually a demon army is made up of 4 regular high class demons and a demon lord. Demon lords in particular are basically invincible normally, but that’s when the holy sword becomes important, it can kill them. Meanwhile, high class demons can be defeated without it, though with a lot of difficulties. the balance isn’t actually bad at all for humans. Normally, that is… a number of reveals will be made about why things are different for the worse right now, combined with the multiple factors I mentioned.
