I think that Mrs. Loftus is a genuinely kind and caring old woman who takes it upon herself to protect this poor boy. Mrs. Loftus thinks that Huck is a runaway apprentice, and I think that she sympathizes that he wants his own life rather than what he is being forced to do. Mrs. Loftus doesn't want Huck to be punished harshly, and she even tells Huck that if he gets in trouble he can contact her. This helps to support the kindness of Mrs. Loftus' character.