The mouse is an unloved and undesirable creature that cannot make people accept itself even though it is not actually a sin. The mouse that the individual sees in his dream symbolizes the existence of a person who makes himself unhappy and upsets him with his mere existence. Essentially, this is due to the energies not being compatible, not because the other party is at fault. Seeing that he is killing the mouse shows that he has thoughts about how to get rid of that person. Because the individual, whether from the family or from the outside, is very uncomfortable with the existence of this person.