"Homie" is not an expression of Spanish, it is one of English. Generally, when there is more than one person living in a house, and individuals are NOT related by blood (they are not family, that is, it can be an apartment where 3 friends live, or 4 students), 'homie' is a loving expression to call the others, a short way of saying 'homemate' or what is similar in Spanish 'homemate'
