A person who is willing to sacrifice everything, even his/her life, to assume a noble role of a blameless, righteous, virtuous and good person.
Their orientation toward morals would be considered brave and a true champion of achieving good and rightness, almost to be considered god-like in morals.
Most people do not consider moral heroism as obligatory, it is not forced. One dictated by moral heroism binds them self to this contract under personal desire and will only.
Shawn is a moral hero, the true definition of moral heroism, because he has not even considered his own entitlement to his personal belongings or his health. Since he has gave it all away, including his life savings and even his extra organs, to guarantee the maximum good has been achieved, the maximum he is capable of granting.