You might be referring to those with Antisocial Personality Disorder(ASPD), as they lack empathy.
If you're talking about emotion in general, you're looking for apathy.
As for the different/troublesome part of the question, you don't make yourself very clear, but I can tell you that although many people associate ASPD with Psychopathy (a more extreme form of the condition), not all Antisocials are 'troublesome'.
lifeless or we can call it fish lives without water.
So-called "troublesome" verbs are those that are frequently misused. In particular, there are some pairs of verbs that sound similar, but have different meanings. The three classic examples are "sit" and "set", "lie" and "lay" and "rise" and "raise". Another "troublesome" verb pair for some people is "borrow" and "lend"--which have opposite meanings! These are further confused by the extremely common misuse of the noun "loan" in place of the verb "lend".
The episode is called A Gruff Act to Follow
pathos
They are troublesome! They cause violence! They start war with other gangs!
Mood.
deception, hypocrisy
emotion
It's an emotion called jealousy.
Apathy?
A word that expresses emotion is called an "emotion word" or "emotive word." These words convey feelings, moods, and emotional states, such as "joy," "anger," "sadness," or "fear." They are often used in literature, poetry, and everyday language to evoke or communicate emotional responses.
The study of cockroaches is called Blattology. Those who study the cockroaches are called Blattologists. Cockroaches are large insects that can be troublesome.