The first time that you enter Garbage you will run across Yurik being bushwhacked by a trio of bandits. Initially the bandits are logged as neutral loners by your PDA. Rescuing Yurik is not obligatory, there is not even a PDA 'hurry up' to do so; however, rescuing him will win you another friend and help later as you both 'Respond to the call for help' which triggers soon afterwards.