Altruism is human characteristic that can make a person make personal sacrifices for the benefits of to others. It tend to make people who have it become selfless and put their own needs beneath the needs of the group.
This can be seen in Parami's behavior.
She most likely would not get any reward from homeless shelter. Even though it took a lot of time, she choose to does it anyway because she know that it will benefit a lot of people.
