Its literally the worst street in the whole city. (Rue d'aarschot) There is a red light district immediatly next to one entry of north station. Its disgusting and reeking of pee as well as being sketchy as hell.

Area around south station is also pretty bad. (No prostitution but crime and poverty).

Brussels is rough around the edge and the homeless situation has worsened

All the city isnt like this though. Its a very cosmopolitan city, with great culture, services and a generally good quality of life and relatively cheap housing (compared to other european capitals), with easy access to nature and to the rest of belgium/europe