Evil isn't the desire to harm others. Devils don't desire to claim people's souls for the lulz, they do it for power. Everything they do is to gain power, for their own benefit. They don't care if the souls will become lemures or a snack, they just try to convince people and scheme for their own benefit anyway.

Demons are way more brutal, they don't really gain pleasure from pain per-se, they also want power, but their approach is way more direct. If they can gain power by killing all those people and bathing in their blood, thay will forcefully do it, not by deceiving the human through a shitty contract, but by forcing their power.

Devils are LE, demons are CE. All in all, evil is the disregard of moral consequences when finding ways to benefit yourself.

Deceiving someone to sign a shitty contract so they now must slave away for you? LE.

Kidnapping someone and forcing them to do stuff to your benefit? CE.

Reaching a fair accord so that you allow people in need to work for you for a fair price, where both parties give a bit so no one is really getting taken advantage off? Either LG or LN depending on the context.

Offering to kill the bad monster that is terrorising the town for free, and disregarding the lucrative offers from it because it's the right thing to do? Any good alignment.

Any of those people could have desires of harm, it's how they channel their wants that puts them in different places in the alignment chart.