it is for a long time that i have not writting any things here.

the case is happend on my good friend ,she worked in a company for the education training as me before , she is in a position of a consulting teacher ,that is mean if a student you served is successful you will get a percentage from  a sum of money ,all you may know this rule .
i will mark my friend A
her colleague B
her customer of the student C
unforturately ,my friend A served  C for a long time ,C  promise to A when he come to her company he will  pay the money to her for the course he had choosed.  one day ,C come to  shcool (company )and find A ,but A  was not in shcool ,so her colleague C come out and greetting the
C , even the C tell B  he had promise  A he will pay the money to A ,but B tell C i just help A greetting you and  instead of A to get the money from you ,so you do not worry about this .

After this ,C had gone .

the next day A know this things ,At first she was very appreciated about what C had done for her and she said  thank you to  C .you know how C reply  ? C said angrily   and  rudely  the customer is mine ,it is none of your business ,B come to here just ask me ,he tell nothing about you .do you know ? so this customer is obvious  mine . after heard this word ,A can not say a word ,when A open her QQ and find the student of B is missing ,she can not find B in her QQ list .

you know what happend , C delete B in A "S QQ ,when A wa s not at her seat , C  in order to  get the percentage  from the sum of money he did so ,and say so many  bad words hurt their relationship of colleague.did it deserved to do ?

how do you think about this things in your work ?
I did to say the  C is small person ?
he do not know how important to bullt the relationship bettwen  the people around him .